Antimicrobial Materials and Interfaces E-Book
241,99 €
Mehr erfahren.
- Herausgeber: Wiley-VCH
- Kategorie: Fachliteratur
- Sprache: Englisch
A review of novel antimicrobial materials remedies for eradication of common and multidrug-resistant bacteria
Antimicrobial Materials and Interfaces covers a wide range of antimicrobial materials with a review of the synthesis, characterization, and applications of each material.
Contributed to by leading experts in the field, Antimicrobial Materials and Interfaces includes information on:
- Cationic and zwitterionic polymers-based antimicrobial materials, zwitterionic polymers as antifouling materials, and superhydrophobic antifouling and antimicrobial materials
- Antimicrobial peptides, protease antibacterial materials, antimicrobial nanometallics, and antimicrobial metal and covalent organic frameworks
- One- and two-dimensional, photothermal, photodynamic, stimuli-responsive, and intelligent antimicrobial materials
- Nitric oxide delivery materials, sonodynamic sterilization materials, and polymer-based antibacterial ureteral stents
- Piezoelectric and photocatalytic materials for antibacterial therapy and microneedle technology for the management of bacterial skin infections
Antimicrobial Materials and Interfaces is an essential reference on promising novel materials for materials scientists and inorganic, bioinorganic, medicinal, polymer, and protein chemists.
Sie lesen das E-Book in den Legimi-Apps auf:
Seitenzahl: 1341
Veröffentlichungsjahr: 2025
Ähnliche
Table of Contents
Cover
Table of Contents
Title Page
Copyright
Preface
Biography
Volume 1
Chapter 1: Cationic Polymers and Their Applications
1.1 Introduction
1.2 Classification and Features of Cationic Polymers
1.3 Summary and Outlook
References
Chapter 2: Design, Synthesis, and Cutting-edge Applications of Novel Cationic Antimicrobial Polymers
2.1 Introduction
2.2 Design and Synthesis of Cationic Antimicrobial Polymers
2.3 Cutting-edge Applications of Cationic Antimicrobial Polymers
2.4 Summary and Outlook
References
Chapter 3: Zwitterionic Polymers-based Antibacterial Surfaces
3.1 Introduction
3.2 Zwitterions and Zwitterionic Polymers
3.3 Characteristics of Zwitterions and Zwitterionic Polymers
3.4 Zwitterionic Polymers-based Antibacterial Surface
3.5 Summary and Outlook
References
Chapter 4: Bifunctional and Smart Antibacterial Surfaces
4.1 Introduction
4.2 Bifunctional Antibacterial Surfaces Based on the “Kill and Resist” Strategy
4.3 Smart Antibacterial Surfaces Based on a “Kill and Release” Strategy
4.4 Summary
Acknowledgments
References
Chapter 5: Superhydrophobic Antifouling and Antimicrobial Materials
5.1 Introduction
5.2 Bioinspired Surfaces
5.3 Theories of Wettability
5.4 Methods for Preparing Superhydrophobic Surfaces
5.5 Factors Influencing Bacterial Adhesion
5.6 Types of Superhydrophobic Antifouling and Antimicrobial Materials
5.7 Application
5.8 Conclusion
References
Chapter 6: Antimicrobial Peptides: From Natural to Synthetic, Conjugated and Polypeptides
6.1 Introduction
6.2 Natural AMPs
6.3 Synthetic AMPs
6.4 Conjugation of AMPs with Other Molecules
6.5 AMP-mimic Polymers/Polypeptides
6.6 Remarks
References
Chapter 7: Protease Antibacterial Materials
7.1 Introduction
7.2 Protease Antibacterial Materials and Potential Applications
7.3 Challenges and Limitations
7.4 Conclusion and Future Perspectives
Acknowledgments
References
Chapter 8: Antimicrobial Nanometallics
8.1 Introduction
8.2 Antimicrobial Resistance: A Global Peril
8.3 Nanotechnology Unleashed: A Frontier in the Battle Against Microbial Threats
8.4 Antimicrobial Nanometallics
8.5 Gold Nanoparticle
8.6 Titanium Oxide and Titanium Dioxide
8.7 Zinc Oxide
8.8 Copper Oxide
8.9 Magnesium Oxide
8.10 Nitric Oxide
8.11 Iron Oxide
8.12 Selenium Oxide
8.13 Bimetallic Nanoparticles
8.14 Future Perspectives
8.15 Conclusion
References
Chapter 9: Antimicrobial Metal-organic Frameworks
9.1 Introduction
9.2 Applications of MOF-based Antimicrobial Substrates for Biomedical Engineering
9.3 Conclusion
Acknowledgments
References
Chapter 10: One-dimensional Antibacterial Materials
10.1 Introduction
10.2 Typical 1D Antibacterial Nanomaterials
10.3 Synthesis of 1D Antibacterial Nanomaterials
10.4 Physicochemical Antimicrobial Mechanisms of 1D Antibacterial Nanomaterials
10.5 Biomedical Applications of 1D Antibacterial Nanomaterials
10.6 Conclusion and Future Perspectives
References
Volume 2
Chapter 11: Two-dimensional Antimicrobial Materials
11.1 Introduction
11.2 Graphene
11.3 Preparation of Graphene
11.4 Properties of Graphene
11.5 Graphdiyne
11.6 Preparation of GDY
11.7 Properties of GDY
11.8 Antimicrobial Applications of GDY
11.9 Preparation of 2D TMDs
11.10 Properties of 2D TMDs
11.11 Antimicrobial Applications of 2D TMDs
11.12 Preparation of BP
11.13 Properties of BP
11.14 VP
11.15 Properties of VP
11.16 MXenes
11.17 Properties of MXenes
11.18 Summary and Future Perspective
References
Chapter 12: Nitric Oxide Delivery Materials for Antimicrobial Applications
12.1 Introduction
12.2 Antimicrobial Mechanism of NO
12.3 NO Donor and Its Responsive Release
12.4 NO Delivery Systems for Antimicrobial Therapy
12.5 Conclusion
References
Chapter 13: Recent Progress of Biomaterials for Antibacterial Photodynamic Therapy
13.1 Introduction
13.2 Small-Molecule Photosensitizers
13.3 Nanomaterials
13.4 Hydrogels
13.5 Dressings
13.6 Other Materials
13.7 Conclusion
References
Chapter 14: Antibacterial Photothermal Materials: Mechanism, Classification, and Applications
14.1 Introduction
14.2 Mechanism of Antibacterial Photothermal Therapy
14.3 Antibacterial Photothermal Materials
14.4 Photothermal-based Synergetic Therapy
14.5 Conclusion
Acknowledgment
References
Chapter 15: Sonodynamic Sterilization Materials
15.1 Introduction
15.2 Potential Antimicrobial Mechanisms and Advantages of SDT
15.3 Categories and Synthesis of Sonodynamic Sterilization Materials
15.4 Application of Sonodynamic Sterilization Materials
15.5 Conclusion and Perspectives
References
Chapter 16: The Role of Piezoelectric Materials for Antibacterial Therapy
16.1 Introduction
16.2 Background of Antibacterial Therapy
16.3 Piezoelectric Materials in Antibacterial Therapy
16.4 Applications and Strategies
16.5 Biocompatibility and Safety
16.6 Challenges and Future Perspectives
16.7 Summary
References
Chapter 17: Advancements in Photocatalytic Antimicrobial Materials: Synthesis, Mechanisms, and Applications
17.1 Introduction
17.2 Photocatalysis: Background and Fundamental Concepts
17.3 Photocatalytic Mechanisms in TiO
2
Interfaces—From UV to Visible Light Activation
17.4 The Role of ROS in Antimicrobial Photocatalysis
17.5 Applications of Antimicrobial Photocatalysis
17.6 Key Criteria for Synthesis of Photocatalysts Targeting Biomedical Applications
17.7 Conclusion
References
Chapter 18: Microneedle Technology for the Management of Bacterial Skin Infections
18.1 Introduction
18.2 The Development of Microneedle Technology
18.3 Classification and Characteristics of MNs
18.4 Advantages of MNs in Managing Skin Infections
18.5 MNs Used to Treat Skin Infections without Wounds
18.6 MNs Used to Treat Infectious Non-diabetic Wounds
18.7 MNs Used to Treat Infectious Diabetic Wounds
18.8 Theranostic MNs for Intelligent Management of Infectious Wounds
References
Chapter 19: Antimicrobial Surfaces for
In vivo
Applications
19.1 Introduction
19.2 Strategies for Fabrication of Antimicrobial Surfaces
19.3 Conclusion and Future Perspectives
References
Chapter 20: Polymer-based Antibacterial Ureteral Stents: A Critical Discussion
20.1 Introduction
20.2 Ureteral Stenting Procedure
20.3 Performances of Polymers Modified Antibacterial Ureteral Stents from Literature
20.4 Conclusion
Acknowledgments
References
Index
End User License Agreement
List of Illustrations
Chapter 1
Figure 1.1 Overview of the categorization of cationic polymers and current appl...
Figure 1.2 Destruction of the cell membrane by quaternary ammonium-based polyme...
Figure 1.3 Overview of the interaction of guanidinium-based polymers with biofi...
Figure 1.4 Applications of imidazolium-based polymer in different fields. (a) Stainless...
Figure 1.5 Schematic representation of PCL-coated membranes used in industrial ...
Figure 1.6 Illustration of dendritic polymer interactions with bacterial biofil...
Figure 1.7 Illustration of hybrid systems combining cationic polymers and other...
Chapter 2
Figure 2.1 Common types of cationic moieties in antimicrobial polymers.
Figure 2.2 (a) Structures of cationic antimicrobial polyurethanes: PQA,...
Figure 2.3 (a) Synthetic route of guanidinium-functionalized polycarbonates and...
Figure 2.4 (a) Antibacterial polyphosphonium containing hydrophilic groups, com...
Figure 2.5 Sequence control in cationic antimicrobial polymers: two primary app...
Figure 2.6 (a) Schematic representation of the synthetic route for cyclic catio...
Figure 2.7 (a) Schematic representation of the synthesis of macromonomers via R...
Figure 2.8 (a) Schematic representation and TEM image of star-shaped cationic a...
Figure 2.9 (a) Structure and design features of fifth-generation cationic bis-M...
Figure 2.10 Mechanisms of cationic polymers in enhancing antibiotic efficacy: (a...
Figure 2.11 Mechanisms of LPS neutralization or clearance by cationic polymers.
Figure 2.12 Illustration of the membrane structures of mammalian cells, Gram-pos...
Chapter 3
Figure 3.1 Proposed schematic of zwitterion dipole moment and hydration. Left: ...
Figure 3.2 Schematic illustration of major stages involved in biofilm formation.
Figure 3.3 (a) The scheme of grafting pSBMA on the cotton fabric via surface-in...
Figure 3.4 (a) The schematic illustration of the proposed antifouling strategy ...
Figure 3.5 (a) Schematic of the preparation of antifouling surface by TA-inspir...
Figure 3.6 (a) Schematic illustration of the construction of the p(SBMA-co-NHSM...
Figure 3.7 Schematic illustration of surface initiated ATRP on the PET substrate.
Figure 3.8 (a) Structural formula of PMMMSi. (b) Schematic of the modification ...
Figure 3.9 Schematic illustration of the preparation process of the coating on ...
Figure 3.10 Schematical illustration for preparing covalently bonded LbL surface.
Figure 3.11 Illustrations and synthesis scheme of antifouling and nitric oxide (...
Figure 3.12 Schematic illustration of the fabrication of polyDVBAPS-g-TCS brushe...
Figure 3.13 Schematic illustration of (a) the preparation of pH-responsive zwitt...
Figure 3.14 The brief mechanism of “bacteria-killing,” “bacteria-releasing” and ...
Figure 3.15 (a) Switching schematic between the anti-fouling, zwitterion chemist...
Chapter 4
Figure 4.1 Representation of the (a) preparation of the mixed polyHEAA/polyMETA...
Figure 4.2 Schematic illustration of (a) grafting two different polymer brushes...
Figure 4.3 (a) Chemical attachment of an anti-adhesive hydrogel embedded with A...
Figure 4.4 Fabrication of a bifunctional antibacterial hydrogel coating with se...
Figure 4.5 Preparation of an antibacterial HA/PAMAM multilayered film via LBL a...
Figure 4.6 (a) Surfaces grafted with nanopatterned polyNIPAAm brushes and tethe...
Figure 4.7 Schemes of (a) a pH-responsive antibacterial surface with hierarchic...
Figure 4.8 Schemes of pH-responsive antibacterial surfaces that kill bacteria i...
Figure 4.9 Schemes of (a) an electric-assisted salt-responsive antibacterial su...
Figure 4.10 Schemes of (a) an antibacterial hydrogel that can switch from ...
Figure 4.11 Schemes of a sugar-responsive antibacterial surface based on the...
Figure 4.12 Scheme of a smart antibacterial surface with triple stimuli responsivity.
Chapter 5
Figure 5.1 Some organisms in nature that possess superhydrophobic surfaces. (a)...
Figure 5.2 (a) Diagram of equilibrium contact angle () formed at ...
Figure 5.3 SEM images of the fractal AKD surface: (a) top view and (b) cross-section.
Figure 5.4 Water droplets on AKD surfaces: (a) fractal AKD surface () and...
Figure 5.5 Tilt-view photographs of water droplets on: (a) untreated carbon fab...
Figure 5.6 SEM images of dendritic gold clusters formed on an ITO electrode mod...
Figure 5.7 Preparation of superhydrophobic films based on raspberry-like particles.
Figure 5.8 Hindering microbial adhesion through an entrapped air barrier. (a) C...
Figure 5.9 Fabrication of a PDMS-ZnO/Au superhydrophobic photodynamic antibacte...
Figure 5.10 Schematic illustration of different dual-function superhydrophobic b...
Figure 5.11 The antimicrobial performance of different samples against
S. aureus
...
Figure 5.12 The antimicrobial performance of different samples against
P. gingiv
...
Chapter 6
Figure 6.1 Two types of antibacterial mechanisms by AMP. The membrane action me...
Figure 6.2 Conjugation of AMP with antibiotics using a cleavable linker, showin...
Figure 6.3 Conjugation and delivery of AMP with nanoparticles aim to improve st...
Figure 6.4 Conjugation of AMP with chitosan to obtain peptidopolysaccharides fo...
Chapter 7
Figure 7.1 Various types of protease enzymes used in different industries (Note...
Figure 7.2 Future application of antibacterial proteases in the development of ...
Figure 7.3 The correlated accomplishments of UNSDG Agenda: 2030 in partnerships...
Chapter 8
Figure 8.1 Causes of emerging diseases.
Figure 8.2 Types of emerging diseases based on mode of transmission.
Figure 8.3 Factors in antibiotic resistance spread: human medicine, animal farm...
Figure 8.4 Various routes for the antimicrobial activity of nanoparticles (orga...
Figure 8.5 Ag-based synergistic antimicrobial composites [144].
Chapter 9
Figure 9.1 Representative MOF structures reported by many groups.
Figure 9.2
In vivo
wound healing results and interpretation. (a) Postimplantati...
Figure 9.3 The detailed
in vitro
antibacterial studies, including kinetics agai...
Figure 9.4 Characterization and physicomechanical properties of MOF-based compo...
Figure 9.5 Subcellular localization studies of NU-901-based MOFs nanoparticles ...
Figure 9.6 Representative photomicroscopic images and mechanical properties of ...
Figure 9.7 Various characteristics and properties, such as printing ability and...
Chapter 10
Figure 10.1 A summary of 1D antibacterial nanomaterials including typical exampl...
Figure 10.2 Model and typical representation of 1D antibacterial nanomaterials w...
Figure 10.3 Top–down and bottom–up synthesis methods of nanomaterials.
Figure 10.4 Antibacterial mechanisms of nanomaterials.
Figure 10.5 Photothermal antibacterial mechanisms of nanomaterials. (a) Photothe...
Figure 10.6 Mechanisms of photocatalytic (a) and photodynamic (b) antibacterial.
Figure 10.7 Synergistic antibacterial effects. (a) Light-induced/physical cuttin...
Figure 10.8 Biomedical applications of 1D antibacterial nanomaterials in biosens...
Figure 10.9 Biomedical applications of 1D antibacterial nanomaterials in bioimag...
Figure 10.10 Biomedical applications of 1D antibacterial nanomaterials in drug de...
Figure 10.11 Biomedical applications of 1D antibacterial nanomaterials in tumor t...
Chapter 11
Figure 11.1 Scheme diagram of various 2D antimicrobial materials.
Figure 11.2 (a) The structure of graphene.
Figure 11.3 (a) Schematic representation of nanoindentation on a suspended graph...
Figure 11.4 (a) The synthesis process of GO-metal. (b) Photographs of antimicrob...
Figure 11.5 (a) Schematic diagram of the structural model of GDY.
Figure 11.6 (a) The energy band structure of GDY [52].
Figure 11.7 (a) 2H, 3R, 1T, and 1T′ MoS
2
atomic structures.
Figure 11.8 (a) Schematic representation of ligand-induced MoS
2
exfoliation and ...
Figure 11.9 (a) Monolayer BP and its cell structure.
Figure 11.10 (a) Synthetic route for PL-n. (b) Photothermal performance of PL-n. ...
Figure 11.11 (a) The structure of VP. (b) Layer structure of VP. (c) SEM image of...
Figure 11.12 (a) Three MAX (MXene) structures.
Figure 11.13 (a) Schematic representation of the synthesis of Ti
3
CN MXene. (b) Th...
Figure 11.14 (a) The synthesis process of MXene-AuNCs. (b) Fluorescence images of...
Chapter 12
Figure 12.1 Antibacterial mechanism of NO: (a) Bacterial cell membranes destroye...
Figure 12.2 The mechanism of NO dispersal biofilm [13] / with permission of Else...
Figure 12.3 Different types of NO donors, including NONOate, RSNO, furoxans, met...
Figure 12.4 NO delivery polymer nanomaterials constructed based on controllable radical poly...
Figure 12.5 Strategies for the preparation of NO delivery implant materials. (a) Preparation...
Figure 12.6 NO-releasing hydrogel dressing: (a) The L-Arg@Hydrogel/H
2
O
2
...
Figure 12.7 Preparation of NO-releasing MN for treatment of wound infections: (a) NIR-regula...
Chapter 13
Figure 13.1 Schematic illustrating the categories and applications of biomateria...
Figure 13.2 Schematic showing the preparation of H-CDs and their application for...
Figure 13.3 (a) Schematic depicting the synthesis of HA-Ce6-MNZ NPs. (b) Schemat...
Figure 13.4 Schematic showing the preparation of the riboflavin-loaded supramole...
Figure 13.5 Schematic illustrating the synthesis of 4OI–BP@Gel with multifunctio...
Figure 13.6 (a) Schematic showing the energy transfer mechanism of the ELDT gel....
Figure 13.7 Schematic diagram showing the preparation route of Ti-U@SnS
2
/I and i...
Chapter 14
Figure 14.1 Three mechanisms underlying the photothermal effect: (a) plasmonic l...
Figure 14.2 Schematic diagram illustrating the impact of various temperature gra...
Figure 14.3 Various PTMs for antibacterial applications.
Figure 14.4 Schematic diagram of (a) Ag-based PTMs.
Figure 14.5 Schematic diagram of aggregation, sterilization, and circulation pro...
Figure 14.6 Representative structures of organic small molecules and polymers se...
Figure 14.7 PLNP@PANI-GCS as PTMs for antibacterial PTT. (a) Schematic illustrat...
Figure 14.8 Illustration of other PTMs for antibacterial PTT. (a) Preparation of...
Figure 14.9 Other therapeutic modalities combined with PTT for synergistic infec...
Figure 14.10 Mechanism of ROS production induced by (a) PDT.
Figure 14.11 The comparison between PDT and SDT for efficient disease treatment.
Figure 14.12 Schematic representation of RGD-CO@MPDA-Ti implant for enhancing inf...
Chapter 15
Figure 15.1 Illustration of potential antimicrobial mechanisms of sonodynamic st...
Figure 15.2 Chemical structures of organic sonosensitizers.
Figure 15.3 Liposomes as delivery systems of sonodynamic sterilization materials...
Figure 15.4 Polymer nanoparticles as delivery systems for sonodynamic sterilizat...
Figure 15.5 Mesoporous and 2D materials as delivery systems for sonodynamic ster...
Figure 15.6 Sonodynamic sterilization materials for the treatment of skin infect...
Figure 15.7 Sonodynamic sterilization materials for the treatment of implant inf...
Figure 15.8 Sonodynamic sterilization materials for the treatment of bone and lu...
Chapter 16
Scheme 1 Schematic diagram of different piezoelectric materials for bacterial...
Figure 16.1 (a) The mechanism of piezocatalytic bacterial degradation mediated b...
Figure 16.2 Classification of different types of piezoelectric materials.
Figure 16.3 (a) The diagram depicts the osteomyelitis therapy process utilizing ...
Figure 16.4 (a) Scanning Electron Microscopy (SEM) and Energy-Dispersive X-ray (EDX) analysi...
Figure 16.5 (a) This schematic illustrates a flexible ultrasonic device with...
Figure 16.6 (a) (a) The preparatory procedure and (b) Arranged antibacterial mec...
Figure 16.7 (a) (a) A conventionalized depiction of the high-speed electrospinni...
Figure 16.8 (a) Nanostructured piezotronic surface construction on Ti. (b) In...
Figure 16.9 (a) Development of a microfluidic reactor for the controlled product...
Figure 16.10 (a) A schematic representation of the synthesis of BTO@ZIF-8/CIP NCs...
Figure 16.11 (a) Schematic representation of the prepared immobilized microcapsul...
Figure 16.12 (a) Schematic representation of the targeted photoactivatable nanoco...
Figure 16.13 (a) Illustration depicting the experimental study’s concept. (b) Sca...
Figure 16.14 (a) Illustration depicting the Se-doped piezoelectric implant induci...
Chapter 17
Figure 17.1 Schematic figure illustrating the photocatalysis mechanism, which in...
Figure 17.2 Mechanisms of microbial damage via photocatalysis. When the photocat...
Figure 17.3 Schematic figure illustrating the key criteria for biomedical photoc...
Chapter 18
Figure 18.1 An overview of MNs used for managing skin infections.
Figure 18.2 Schematic illustrating the major events in the development of MNs.
Figure 18.3 Schematic illustrating different types of MNs.
Figure 18.4 Schematic illustrating how MNs increase the permeation of antimicrob...
Figure 18.5 (a) Development of bioinspired OASM for accelerating the healing of ...
Figure 18.6 (a) The diagram of Fe-Se-HA MN double-layer MNs and the MN-based mag...
Figure 18.7 (a) Schematic illustrating the aminobenzeneboronic acid-modified gol...
Figure 18.8 (a) Porous and hollow structures inspired by the structure and biolo...
Chapter 19
Figure 19.1 Schematic representation of anti-adhesive surface with (a) a layer o...
Figure 19.2 Schematic representation of contact-killing antimicrobial surfaces w...
Figure 19.3 Schematic representation of release-killing antimicrobial surfaces w...
Figure 19.4 Schematic representation of antimicrobial surfaces with bactericidal...
Figure 19.5 Schematic representation of smart antimicrobial surfaces with (a and...
Figure 19.6 Schematic representation of smart antimicrobial surfaces with switch...
Chapter 20
Figure 20.1 Polaris
TM
Ultra soft and firm ureteral stent by Boston Scientific.
Figure 20.2 A ureteral JJ-stent showing the connection between kidney and urinar...
Figure 20.3 Comparative study of ZB particles for 24 hours. (a) Bacterial growth...
Figure 20.4 Bacterial assessment by polymer and copolymer activity. (a) Bacterio...
Figure 20.5 (a) Antibacterial performance of control (bare), PPDPA@CU-75, and PD...
Figure 20.6 (a) Ag@Au NP- FMBUS based polymer stent performance on
E. coli
. (b) ...
Figure 20.7 Antibacterial mechanism of Ag@Au NP- FMBUS based polymer stent by pr...
Figure 20.8 Time-dependent antibacterial assessment of Ag@Au NP- FMBUS based pol...
Figure 20.9 (a) Comparative study of blank, PLCL5050, PLCL5050-CIP against
E. co
...
List of Tables
Chapter 2
Table 2.1 Structures of cationic monomers and biological activities of their c...
Table 2.2 Cationic antibacterial polymers formed via
in situ
generation of cat...
Table 2.3 Structures and biological activities of cationic polymers synthesize...
Chapter 3
Table 3.1 Molecular structure of zwitterions.
Chapter 6
Table 6.1 Types of natural antimicrobial peptides and their characteristics.
Table 6.2 Types of AMP conjugation.
Chapter 7
Table 7.1 Antibacterial protease uses and mechanisms in various industries.
Table 7.2 Immobilization/Encapsulation of biocatalytic protease used in variou...
Chapter 8
Table 8.1 Assorted antibiotics employed in medical practice.
Table 8.2 The mechanisms and resistance of key classes of antimicrobial agents...
Chapter 10
Table 10.1 Advantages and disadvantages of main preparation methods for 1D anti...
Chapter 13
Table 13.1 Summary of the representative small-molecule photosensitizers (PSs) ...
Table 13.2 Summary of the current progress of antimicrobial nanoplatforms as ca...
Chapter 16
Table 16.1 Different piezoelectric materials and their piezo-responsive properties.
Chapter 19
Table 19.1 Typical anti-adhesive coatings.
Table 19.2 Typical contact-killing antimicrobial surfaces.
Table 19.3 Typical release-killing antimicrobial surfaces.
Table 19.4 Typical bifunctional antimicrobial surfaces.
Table 19.5 Typical smart responsive antimicrobial surfaces.
Chapter 20
Table 20.1 Summary of the polymeric-modified antibacterial stents.
Guide
Cover
Table of Contents
Title Page
Copyright
Preface
Biography
Begin Reading
Index
End User License Agreement
Pages
i
ii
v
vi
vii
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
524
525
526
527
528
529
530
531
532
533
534
535
536
537
538
539
540
541
542
543
544
545
546
547
548
549
550
551
552
553
554
555
556
557
558
559
560
561
562
563
564
565
566
567
568
569
570
571
572
573
574
575
576
577
578
579
580
581
582
583
584
585
586
587
588
589
590
591
592
593
594
595
596
597
598
599
600
601
602
603
604
605
606
607
608
609
610
611
612
613
614
615
616
617
618
619
620
621
622
623
624
625
626
627
628
629
630
631
632
633
634
635
636
637
638
639
640
641
642
643
644
645
646
647
648
649
650
651
652
653
654
655
656
657
658
659
660
661
662
663
664
Antimicrobial Materials and Interfaces
Synthesis, Characterization, and Applications
Volumes 1–2
Edited by
En-Tang Kang
Southwest University
Liqun Xu
Southwest University
Peng Li
Northwestern Polytechnical University
Editors
Prof. En-Tang Kang
Southwest University
No.2 Tiansheng Road
Chongqing
CH, 400715
Prof. Liqun Xu
Southwest University
No.2 Tiansheng Road
Chongqing
CH, 400715
Prof/Dr. Peng Li
Institute of Flexible Electronics
Northwestern Polytechnical University, Xi’an, China
Cover Design: Wiley
Cover Image: © Christoph Burgstedt/stock.adobe.com
All books published by WILEY-VCH are carefully produced. Nevertheless, authors, editors, and publisher do not warrant the information contained in these books, including this book, to be free of errors. Readers are advised to keep in mind that statements, data, illustrations, procedural details or other items may inadvertently be inaccurate.
Library of Congress Card No.: applied for
British Library Cataloguing-in-Publication Data
A catalogue record for this book is available from the British Library.
Bibliographic information published by the Deutsche Nationalbibliothek
The Deutsche Nationalbibliothek lists this publication in the Deutsche Nationalbibliografie; detailed bibliographic data are available on the Internet at http://dnb.d-nb.de.
© 2025 Wiley-VCH GmbH, Boschstraße 12, 69469 Weinheim, Germany
The manufacturer’s authorized representative according to the EU General Product Safety Regulation is Wiley-VCH GmbH, Boschstr. 12, 69469 Weinheim, Germany, e-mail: [email protected].
All rights reserved (including those of translation into other languages, text and data mining and training of artificial technologies or similar technologies). No part of this book may be reproduced in any form – by photoprinting, microfilm, or any other means – nor transmitted or translated into a machine language without written permission from the publishers. Registered names, trademarks, etc. used in this book, even when not specifically marked as such, are not to be considered unprotected by law.
Print ISBN: 9783527353828
ePDF ISBN: 9783527846962
ePub ISBN: 9783527846955
oBook ISBN: 9783527846979
Preface
Introduction of antimicrobial coatings on material surfaces could provide additional protection against life-threatening bacterial infections. However, extensive efforts to develop new antibiotics are lagging behind the rapid spread of multidrug-resistant pathogens. As such, there is strong motivation to develop alternative remedies that bypass the resistance mechanisms and are able to treat bacterial infections. This book will put forward a library of novel antimicrobial materials remedies, beyond antibiotics, for the eradication of multidrug-resistant bacteria. As a rapidly growing frontier field in healthcare materials science, the topics included in this book will generate significant attention from a variety of research fields and provide guidelines for those who are entering a related research area/field. Each chapter of this book is devoted to the discussion of a specific category of novel antimicrobial materials that have been designed and developed to combat multidrug-resistant pathogens. This book covers the recent progress in the synthesis, characterization and applications of antimicrobial materials and coatings, including cationic polymers-based antimicrobial materials (Chapters 1 and 2), zwitterionic polymer-based antimicrobial materials (Chapter 3), bifunctional and smart antibacterial surfaces (Chapter 4), superhydrophobic antifouling and antimicrobial materials (Chapter 5), antimicrobial peptides (Chapter 6), protease antibacterial materials (Chapter 7), antimicrobial nanometallics (Chapter 8), antimicrobial metal-organic frameworks (Chapter 9), one-dimensional antibacterial materials (Chapter 10), two-dimensional antimicrobial materials (Chapter 11), nitric oxide delivery materials for antimicrobial applications (Chapter 12), biomaterials for antibacterial photodynamic therapy (Chapter 13), antibacterial photothermal materials (Chapter 14), sonodynamic sterilization materials (Chapter 15), piezoelectric materials for antibacterial therapy (Chapter 16), photocatalytic antimicrobial materials (Chapter 17), microneedle technology (Chapter 18), antimicrobial surfaces for in vivo applications (Chapter 19), and polymer-based antibacterial ureteral stents (Chapter 20). With the chapter contributions from experts in the field, the book is a go-to resource for graduate/research students, materials scientists and engineers, biomedical researchers, healthcare personnel, and industry professionals focusing on antimicrobial/antibacterial materials and applications. The multidisciplinary nature of the book allows it to cater to different readers from different backgrounds. Therefore, the book has been arranged in such a way that each chapter builds on the central theme of antimicrobial effects and yet is largely self-contained and can be read independently.
Editors,
En-Tang Kang
Liqun Xu
School of Materials and Energy
Southwest University, Chongqing, China
Peng Li
Institute of Flexible Electronics
Northwestern Polytechnical University, Xi’an, China
Biography
En-Tang Kang obtained his PhD from the State University of New York at Buffalo in 1983. He is currently a Professor at the School of Materials and Energy at Southwest University in Chongqing, China. He is also an Emeritus Professor in the Department of Chemical & Biomolecular Engineering at the National University of Singapore. His research interests include surface functionalization via molecular design, molecular/polymer electronics, polymers in nanoscience and biomolecular engineering and polymers for environmentally benign applications. He has published more than 750 articles and reviews in international journals, with more than 37 000 citations and an H-index 97. He has also authored/co-authored more than 20 book chapters. He is a Fellow of the Royal Society of Chemistry.
Liqun Xu obtained his bachelor and PhD degrees at Southeast University (2009) and National University of Singapore (2014), respectively. He is currently a Professor of the School of Materials and Energy and Vice Dean of the Office of Scientific Research and Development at Southwest University (SWU) in Chongqing, China. His research interests include surface antibacterial/antifouling modification and preparation of advanced antimicrobial agents. He has published more than 110 articles and reviews in international journals, with more than 6000 citations and an H-index 45. He has also authored/co-authored more than 3 book chapters.
Professor Peng Li earned his bachelor and PhD degrees at Tianjin University (2006) and Nanyang Technological University (2013), respectively. He worked at Xi’an Jiaotong University and Nanjing Tech University as faculty from 2013 to 2018. Currently, he is the director of Xi’an Biomedical Materials Engineering & Technology Research Center, Northwestern Polytechnical University (NPU, China). His research interests are the development of biomaterials and devices for the treatment of diseases, especially infectious diseases caused by pathogenic microbes. He focused on the design and synthesis of antimicrobial peptides and polymers, and the fabrication of antimicrobial coatings for biomedical devices. He has published more than 100 journal papers in Nat. Mater., Sci. Adv., Adv. Mater., Adv. Sci., ACS Nano, etc. He holds 20 Chinese patents and 5 international patents (3 transferred). Email: [email protected]
Chapter 1Cationic Polymers and Their Applications
Guang Yang, Shun Duan, Fu-Jian Xu
State Key Laboratory of Chemical Resource Engineering, Key Laboratory of Biomedical Materials of Natural Macromolecules (Beijing University of Chemical Technology), Ministry of Education, Beijing Laboratory of Biomedical Materials, College of Materials Science and Engineering, Beijing University of Chemical Technology, Beijing, China
1.1 Introduction
Cationic polymers have emerged as a versatile and potent class of antimicrobial agents, particularly in response to the escalating global threat of antimicrobial-resistant bacteria [1]. These macromolecules, characterized by their positively charged functional groups in their main chains and/or side chains, target the negatively charged bacterial cell membranes, causing disruption of cellular integrity and subsequent cell death [2]. Unlike traditional antibiotics that act by targeting specific biochemical pathways, cationic polymers exert their antimicrobial effects through direct physical interactions with bacterial cell membranes. This unique nonspecific mode of action significantly reduces the likelihood of resistance development, positioning cationic polymers as a promising alternative in developing the next-generation of antimicrobial materials [3].
The diversity of cationic polymers in their polymeric structure and composition, encompassing linear, branched, hyper-branched, dendrimer-like, and hybrid systems, has facilitated their adaptability for a wide range of applications [3]. These cationic materials have also demonstrated their remarkable efficacy in preventing and controlling microbial contamination, crossing different fields such as medical device coatings [4], wound dressings [5], environmental water treatment [6], and food packaging [7]. Moreover, customizable chemical structures and functional groups in cationic materials enable precise optimization of their antimicrobial activity, biocompatibility, and environmental sustainability [8, 9], making them invaluable in addressing current challenges in healthcare, industry, and environmental fields [10].
This chapter provides a comprehensive overview of cationic polymers as antimicrobial materials by utilizing insights from some representative research in this field. It begins by defining and classifying cationic polymers, highlighting their structural diversity and functional mechanisms (see Figure 1.1). The subsequent sections categorize the applications of the most studied cationic polymers in various fields according to the referenced previous studies. Each section delves into the specific contributions of cationic polymers from individual studies, concluding with a summary of the advantages, limitations, and future directions for each type of polymer. The chapter concludes with a broad perspective on the challenges and opportunities in this field, emphasizing the potential of cationic polymers to reshape global antimicrobial strategies.
Figure 1.1 Overview of the categorization of cationic polymers and current applications in modern medicine, industry, and agriculture. Of note, R and R3 can be adjusted according to the application scenario of the cationic polymers, which can be hydrophobic alkyl, hydrophilic polyethylene glycol, or other functional groups. In general, R1 can be the quaternary ammonium salts, guanidine, imidazole, and other cationic groups. While R2 can be halides, inorganic fluorides, perfluorinated sulfonamides, or other ionic groups.
Source: Alexander/Adobe Stock Photos
1.2 Classification and Features of Cationic Polymers
Cationic polymers are of great significance for the development of novel antimicrobial agents, both to combat the growing trend of antimicrobial-resistant microorganisms, and to find materials useful for the prevention or treatment of bacterial infections with more specific characteristics in different scenarios. In this section, due to the diversity of cationic polymers, an overview of the most common types of cationic polymers with antibacterial activity is presented, and some representative and recent examples from individual groups are also discussed to further clarify their action mechanisms and practical applications.
1.2.1 Quaternary Ammonium-based Polymers
Quaternary ammonium-based polymers, as applied materials in the field of antimicrobial polymers, are among the most extensively studied in the research community due to their broad-spectrum antimicrobial activity. These type of polymers are permanently positively charged independent of pH value due to their cationic quaternary ammonium moieties and thus can strongly interact with the negatively charged bacterial membranes [11]. This interaction is able to cause irreversible damage to the membrane structure of bacterial cells and subsequent cell death [12]. To our best knowledge, hitherto bacterial resistance to these polymers has not been reported and is generally considered highly unlikely to develop [13]. Hence, quaternary ammonium-based polymers have been utilized across a range of applications, including medical devices, water treatment, food packaging, and textiles.
1.2.1.1 Chemical Structure and Mechanism of Action
Quaternary ammonium-based polymers are relatively simple to prepare, either through the alkylation of polymers containing amine groups or through the polymerization of monomers with ammonium [14]. Although these polymers may differ in terms of polymerization degree or their monomer structure, some studies have focused on researching and summarizing the relationship between their chemical structure and antibacterial performance. First, the strongly positive charges allow cationic polymers themselves to bind onto the negatively charged bacterial cell membrane through electrostatic interaction, during which the density of the positive charge plays a critical role in determining the strength and efficiency of this binding (see Figure 1.2) [15]. Then, as another important parameter, the hydrophobic alkyl chains that are supported by ammonium nitrogen insert into the phospholipid bilayer via hydrophobic and electrostatic interaction. That disrupts the ordered arrangement of phospholipids and increases membrane instability and fluidity, leading to pore formation or even complete membrane disintegration, subsequent leakage of cellular components, and eventually bacterial cell death (see also Figure 1.2) [16]. Guided by this mechanism, various cationic polymers have been developed for efficiently preventing or controlling planktonic bacteria- and biofilm-related infections in different fields [17, 18].
Figure 1.2 Destruction of the cell membrane by quaternary ammonium-based polymers in Gram-positive (Gr+) and Gram-negative (Gr−) bacteria. In detail, quaternary ammonium-based polymers disrupt bacterial cell membranes in a three-step process. First, the cationic polymers are electrostatically attracted to the negatively charged bacterial membrane. Then, the hydrophobic segments of the polymers insert and penetrate the lipid bilayer. Finally, these hydrophobic chains destabilize the bilayer through combined electrostatic and hydrophobic interactions, compromising the integrity of the bacterial membrane, cellular contents leakage, and ultimately bacterial cell death.
1.2.1.2 Applications of Quaternary Ammonium-based Polymers
1.2.1.2.1 Medical Devices and Healthcare
Quaternary ammonium-based polymers have been widely used in medical device coatings to prevent biofilm formation and device-associated infections. Implantable devices, such as catheters and orthopedic implants, are highly susceptible to microbial adhesion, colonization, and subsequent biofilm formation after being implanted in the human body, leading to serious, life-threatening bacterial infections and complications. Quaternary ammonium-based polymers can be coated onto the surface of these implantable devices to provide durable antimicrobial activity. For example, the benzyl quaternary ammonium salt containing polycarbonates was coated onto the pristine silicone substrate of the urinary catheter, yielding 5 log-units and 3 log-units killing planktonic Gram-positive Staphylococcus aureus (S. aureus) and Gram-negative Escherichia coli (E. coli), respectively. Moreover, the antibacterial and antifouling activities of this coating remained unchanged after being incubated with S. aureus suspension over 14 days [19]. In addition to this, advanced hydrogels incorporating quaternary ammonium groups were also developed as the antibacterial coating of orthopedic implants, which not only led to a higher than 1 log-unit reduction of two Gram-positive bacterial strains in vitro but also almost fully eradicated the infection from the femoral fracture of intramedullary nail fixation in rats within 42 days [20].
1.2.1.2.2 Water Treatment
In the field of environmental applications, quaternary ammonium-functionalized membranes are highly effective in removing microbial contaminants from drinking water and industrial effluents. Studies have shown epoxy propyl dimethyl dodecyl ammonium chloride-grafted cellulose acetate (CA) membrane (QCA-X) presented an improved filtration capacity and antifouling performance compared with CA membranes in the process of water treatment. Meanwhile, this QCA-X membrane showed excellent antibacterial performance, and the sterilization efficacy against S. aureus and E. coli were both more than 2 log-units even after four repeated antibacterial cycles, highlighting their potential for large-scale water purification systems [21]. Additionally, hybrid membranes combining quaternary ammonium polymers with TiO2 nanoparticles can further enhance pathogen removal efficacy. That can be maintained close to 100% killing efficacy against S. aureus and E. coli and completely inhibited bacterial adhesion and biofilm formation within 7 days, exhibiting great potential to be applied in water treatment [22].
1.2.1.2.3 Food Packaging and Textiles
Quaternary ammonium-based polymers can also be employed in food packaging and textiles due to their broad antibacterial property. As food packaging materials, quaternary ammonium-based polymers can inhibit the growth of spoilage organisms, extend food shelf life, and thus reduce food waste [14, 15]. By incorporating quaternary ammonium salt-modified chitosan into poly(vinyl alcohol) film, the obtained composite films yielded more than 2 log-units killing against planktonic S. aureus and E. coli and significantly extended the storage time of strawberries [23]. In textiles, these polymers have been integrated into fibers to produce antimicrobial fabrics for face masks, hospital bedding, and uniforms. For instance, the nanofibrous filter was fabricated by grafting a layer of poly(2-(dimethyldecyl ammonium) ethyl methacrylate) onto the surface of the metal–organic framework. The composite filter demonstrated a comparable PM filtration efficiency (>95%) to the commercial N95 respirators and was capable of efficiently killing both Staphylococcus epidermidis (S. epidermidis) and E. coli airborne bacteria. Importantly, these textiles retained their antimicrobial efficacy after multiple wash cycles, offering a durable solution for infection control in healthcare settings [24].
1.2.1.3 Recent Advances and Innovations of Quaternary Ammonium-based Polymers
Recent studies have focused on developing biodegradable quaternary ammonium-based polymers to address their environmental concerns. Traditional quaternary ammonium-based polymers are highly effective against Gram-positive and Gram-negative bacterial strains but generally nondegradable, posing a potential pollution risk to a natural ecosystem. Quaternary ammonium-based polymers with enzymatically or acidly degradable linkages have been developed, which allow them to be degraded under different conditions and thus reduce environmental persistence while maintaining their antimicrobial activity. For instance, an acid-cleavable silaketal linkage was introduced of the backbones on quaternary ammonium polymer as a kind of pesticide, enabling control of hydrolysis over the time range of 10 minutes to 3 months according to the conditions of use. Moreover, the pesticide demonstrated outstanding bactericidal and insecticidal properties but became harmless to humans and other organisms after hydrolysis [25].
Another innovative direction is the combination of quaternary ammonium polymers with photodynamic therapy (PDT) agents, creating a dual-action antimicrobial system. Quaternary ammonium-based polymers disrupt bacterial cell membranes through electrostatic interactions and physical damage. PDT agents, after being activated by specific wavelengths of light, produce reactive oxygen species (ROS) that not only damage cell membranes but also oxidize intracellular components like proteins and DNA. This complementary mechanism produces a synergistic antimicrobial effect, significantly enhancing antimicrobial efficacy but without causing bacterial drug resistance. Additionally, the PDT agents allows to be activated precisely and locally by the specific light, making this combination particularly effective for wound infection and skin surface disinfection [26].
Sustainable development is also a key factor to consider when using ammonium-based polymers in any field. Chitosan, a natural and renewable polysaccharide, has attracted more and more attention due to its low cost, biocompatibility, and biodegradability. By chemically modifying chitosan with quaternary ammonium groups, the quaternized polysaccharides not only present the broad-spectrum antibacterial property but also maintain their original excellent performance, such as film forming, biocompatibility, and biodegradation. Hence, quaternized chitosan has been widely applied as wound dressings due to their hemostatic and antibacterial ability, ion exchange membrane for fuel cells due to their high ion conductivity, and so on [27].
1.2.1.4 Advantages and Limitations of Quaternary Ammonium-based Polymers
The rapid development and wide-ranging applications of quaternary ammonium-based polymers are primarily attributed to their two major advantages. First, cationic quaternary ammonium moieties on the backbone or side main of these polymers provide a permanent positive charge, imparting them with long-term and broad-spectrum antimicrobial activity against Gram-positive and Gram-negative bacterial strains, fungi, and some viruses [11, 28]. The contact-killing mechanism composes the second merit of quaternary ammonium-based polymers. Quaternary ammonium-based polymers interact with the negatively charged microbial cell membranes through electrostatic and physical interaction and then disrupt the structural integrity of the cell membrane, significantly reducing the risk of bacterial drug resistance compared to conventional antibiotics [11].
However, adverse effects may occur when concentrations used of these polymers reach a certain level, including severe and chronic toxicity to susceptible organisms, animals, and humans. The cytotoxic effects of these polymers arise primarily from their strong interactions with cell membranes, which makes them effective antimicrobial agents but also poses risks to mammalian cells. It has been reported that a high dose of quaternary ammonium-based polymer can induce dysfunction in mitochondria, leading to cell death and a predisposition toward asthma in healthcare workers [29]. A possible way to solve this problem is through tailoring the structure–activity relationship of these polymers to improve their selectivity and minimize cytotoxicity to normal tissue cells. Meanwhile, they should also be used strictly within the safe dosage, especially in clinical practice.
1.2.2 Guanidinium-based Polymers
Guanidinium-based polymers represent a versatile class of antimicrobial materials, distinguished by their guanidinium functional groups. These polymers exhibit strong antibacterial activity, primarily due to the guanidine groups that carry a positive charge under physiological conditions. That enables strong electrostatic interactions with negatively charged bacterial cell membranes, leading to membrane disruption and bacterial cell death [30, 31].
In addition, guanidine-functionalized polymers have shown the capability to dissociate the formed biofilms, which are microbial communities embedded in a self-produced extracellular polymeric substance (EPS) matrix, adhering to surfaces or interfaces such as medical devices, implants, and wounds. The polymers can penetrate into the depth of the biofilm matrix, destabilize or degrade key components of the EPS, such as polysaccharides and extracellular DNA, and then kill the exposed bacteria inside the biofilm [32].
1.2.2.1 Chemical Structure and Mechanism of Action
Guanidinium-based polymers are characterized by the presence of guanidinium functional groups within their polymeric structure. Guanidine groups are highly basic, with a pKa value of approximately 12.5. This means they retain a positive charge across a broad range of pH levels. Under acidic (pH<7.0) or neutral (pH 7.0) conditions, guanidine is fully or largely protonated and carries strong positive charges, making it effective for bacteria- or biofilm-related infection [33, 34]. Guanidine-based polymers present a dual antibacterial mechanism, primarily driven by their strong cationic nature and hydrogen-bonding capability. These polymers can interact electrostatically with the negatively charged bacterial cell membrane. Meanwhile, due to its planar structure and multiple hydrogen donors, guanidinium groups can also form strong multiple ionic hydrogen bonds with negatively charged or polar moieties in bacterial cell membranes. That leads to severe membrane disruption and subsequently the leakage of intracellular contents, and ultimately bacterial cell death [35, 36]. Additionally, guanidinium-based polymers can also penetrate and accumulate into the biofilms by interacting with the negatively charged EPS of the biofilm. That disrupts the structural integrity of the EPS, making the biofilm matrix more permeable, less stable, or even completely destabilized (see Figure 1.3). This dual mechanism underpins the high efficacy of guanidinium-based polymers against both planktonic bacteria and bacteria in a biofilm mode of growth [37–39].
Figure 1.3 Overview of the interaction of guanidinium-based polymers with biofilm structures, including dispersion of biofilm and subsequent microbial clearance. Bacterial biofilms are complex, three-dimensional communities of microorganisms that are embedded in a self-produced EPS matrix. This matrix is primarily composed of extracellular DNA (eDNA), proteins, and polysaccharides, which provide protection to the bacteria against the immune system and antimicrobial agents. Highly positively charged guanidine-based polymers can interact with the negatively charged components of the EPS matrix, including eDNA, proteins, and polysaccharides through electrostatic, hydrogen bonds, and ionic interactions. These interactions lead to the destabilization and partial degradation of the EPS structure, exposing bacteria inside the biofilm to the external environment. Then, the positively charged guanidinium-based polymers interact with the negatively charged bacterial cell membranes, leading to membrane disruption and cell death.
1.2.2.2 Applications of Guanidinium-based Polymers
1.2.2.2.1 Wound Care and Medical Devices
Guanidinium-functionalized hydrogels have shown remarkable potential in wound care applications. For example, poly(hexamethylene guanidine) hydrochloride was first modified with methacrylic anhydride, which was further polymerized with acrylamide initiated by ultraviolet irradiation to prepare guanidinium-based hydrogels in aqueous medium. The hydrogels demonstrated strong antimicrobial activity against S. aureus and E. coli, yielding a close to 2 log-units reduction against both bacterial strains. Furthermore, due to the chemical bonding of the cationic guanidine segment in the hydrogel backbone, these hydrogels can maintain their antimicrobial activity even after soaking in water for 1 month and washing with water many times [40]. In medical devices, a series of guanidinium-based polymers with different side chain lengths and conformations were synthesized and subsequently grafted to the surface of poly(dimethylsiloxane) substrate. These modified substrates can reduce more than 1 log-unit of both S. aureus and E. coli, and effectively inhibit the formation of the biofilm as well as present good biocompatibility, significantly lowering the incidence of device-associated infections in clinical settings [41].
1.2.2.2.2 In Dental Applications
In dental care, guanidinium-based polymers have shown great potential for eradicating oral bacteria-related infections. The guanidine was covalently conjugated onto polyurethanes through a click reaction. These guanidine-functionalized polyurethanes exhibited strong contact-killing antibacterial activity against both Gram-negative and Gram-positive bacteria. Noteworthily, these polymers can yield a more than 3 log-units reduction against S. aureus that is the one of the main bacteria in oral infection, as well as effectively inhibited the formation of oral bacterial biofilm. Moreover, the covalent conjugation of guanidine onto polyurethanes allowed long-term antimicrobial activity and made them a valuable tool in preventive dentistry disease [42].
1.2.2.2.3 Agricultural Films and Coatings
Guanidinium-based polymers have been widely used in agricultural applications; these materials inhibited the growth of plant pathogens such as Fusarium oxysporum (F. oxysporum) and Xanthomonas campestris, improving crop yield and quality. For example, guanidinium chloride was grafted onto the surface of hydroxyapatite-modified Fe2O3 magnetic nanoparticles, and their antifungal capacity against F. oxysporum which primarily causes vascular wilt diseases in a wide range of crops, was determined and analyzed. According to the experimental result, the product demonstrated excellent eradicating efficacy against F. oxysporum by a very low dosage, presenting the potential of being the alternative antifungal drug to increase the resistance of a wide variety of crop plants. Additionally, guanidinium-functionalized sprays provided prolonged protection against bacterial and fungal infections in post-harvest storage [43].
1.2.2.3 Recent Advances and Innovations
Guanidinium-based polymers have garnered significant attention in recent years due to their wide applications across diverse fields. Recent innovations have focused on designing polymers with optimized chain lengths, balanced ratios of hydrophilic and hydrophobic segments, and tailored charge densities to maximize their antimicrobial efficacy and minimize cytotoxicity to human cells. In the field of drug delivery, guanidinium-based polymers have also demonstrated their ability to form stable complexes with nucleic acids through strong electrostatic interactions for effective gene delivery. Their high transfection efficiency, together with relatively low cytotoxicity, makes them considerable and attractive alternatives to traditional viral vectors or traditional cationic polymers such as polyethyleneimine. Meanwhile, researchers have also developed stimuli-responsive guanidinium-based polymers as the drug carriers that release drugs or genetic material in response to environmental changes such as pH [44], temperature [45, 46], or redox potential [31]. These innovations improve therapeutic efficacy and reduce their side effects on normal tissue cells.
Applications of guanidinium-based polymers in the environmental field have also made rapid progress. Due to their strong binding affinity with anionic pollutants such as phosphates, sulfates, and organic dyes, these polymers are being developed as highly efficient adsorbents for water purification [47–52]. Another innovation involves the integration of guanidinium-based polymers with photothermal therapy (PTT) agents, creating multifunctional materials for eradicating bacterial infection and promoting tissue regeneration. The combined system not only effectively eliminates bacteria by direct interaction with guanidinium groups, but also promotes wound healing by enhancing blood circulation and tissue repair processes through localized heating effects of PTT agents under specific light irradiation [53, 54].
1.2.2.4 Advantages and Limitations
Guanidinium-based polymers have drawn increasing interest for their diverse applications due to their unique molecular structures and highly effective antibacterial properties. Guanidinium groups have a high positive charge density, allowing these polymers to interact with and disrupt negatively charged bacterial membranes effectively. This mechanism makes them highly efficient against a broad spectrum of microorganisms, including multidrug-resistant strains, and thus applies in various fields such as biomedicine and environmental engineering [55, 56].
However, there also are some limitations that need to be addressed to broaden their practical applications and achieve clinical translation. For example, in biomedical applications, guanidinium-based polymers can be effective as antimicrobial agents and delivery systems, but can also exhibit potential toxicity toward mammalian cells at higher concentrations, causing unintended side effects, such as inflammation and excessive immune responses [57, 58]. In addition, the introduction of guanidinium groups often requires complex and multi-step chemical processes, which can be costly and time-consuming. Lastly, the long-term environmental impact of degradation products from guanidinium-based polymers remains poorly understood. If not properly designed, these polymers may persist in the environment and potentially contribute to environmental pollution [59]. Thus, efforts to enhance their selectivity and simplify manufacturing processes are crucial for expanding their applications.
1.2.3 Imidazolium-based Polymers
Imidazolium-based polymers are a class of cationic materials characterized by the presence of imidazolium functional groups. The group is a five-membered ring containing a nitrogen atom with a positive charge, which confers a unique combination of hydrophobic and cationic properties. This unique combination enables imidazolium-based polymers to interact effectively with hydrophobic substances as well as negatively charged entities like bacterial membranes, anionic contaminants, and some greenhouse gases, making them highly effective in a wide range of applications, including medical, environmental, and industrial applications (see Figure 1.4) [60].
Figure 1.4 Applications of imidazolium-based polymer in different fields. (a) Stainless-steel mesh coated with imidazolium-based polymers has high water flux and oil separation efficiency as well as superb antibacterial and anti-biofouling activity against both Gram-positive and Gram-negative bacteria. (b) A low dose of imidazolium-based resin presents a strong ability to prevent the formation of biofilm.
Source: Reproduced with permission of the American Chemical Society [66].
1.2.3.1 Chemical Structure and Mechanism of Action
Imidazolium-based polymers are prepared by direct polymerization of imidazolium-containing monomers and post-polymerization modification [61, 62]. The imidazolium group, containing an aromatic heterocyclic ring with a positive charge, interacts strongly with negatively charged bacterial membranes. This interaction destabilizes the lipid bilayer, causing membrane disruption and eventual cell death. Additionally, the hydrophobic nature of the imidazolium group facilitates deeper penetration into the lipid bilayer, enhancing its antimicrobial efficacy. Meanwhile, imidazolium-based polymers can also induce oxidative stress in microbial cells by disrupting intracellular components like DNA and proteins, further contributing to their bactericidal activity [63, 64].
1.2.3.2 Applications of Imidazolium-based Polymers
1.2.3.2.1 Medical Applications
Imidazolium-based polymers have been extensively used in medical settings due to their potent antimicrobial properties and compatibility with other functional materials. For instance, hydrogels incorporating imidazolium-functionalized nanoparticles demonstrated enhanced wound healing in preclinical models. Imidazolium-based polymer microspheres were prepared through emulsion polymerization. Subsequently, these microspheres were integrated into a gelatin methacryloyl-polyethylene glycol hydrogel. The composite hydrogels can yield close to 2 log-unit reduction of both S. aureus and E. coli, and maintain a minimal cytotoxicity and hemolysis activity. Moreover, the hydrogels can also facilitate the migration of human skin fibroblasts and human umbilical vein endothelial cells and promote osteogenic differentiation, suggesting the potential applications of these hydrogels in wound infection and bone repair [65]. In dental care, the imidazolium-containing resin was incorporated into a methacrylate-based scaffold using a simplified condensation reaction to prevent the fouling of oral pathogens like Streptococcus mutans (S. mutans). Only 2% inclusion of imidazolium moiety can result in superior bioactivity with minimal cytotoxicity without compromising the mechanical integrity of the restorative material. Moreover, it can effectively inhibit the adhesion, colonization, and subsequent formation of S. mutansbiofilms over a period of 67 hours, which may serve as a platform for long-term protection against plaque formation and associated diseases [66].
In advanced drug delivery systems, imidazolium-functionalized polymers have been employed as carriers for delivering antibiotics and other therapeutic agents. These systems have been engineered into smart nanocarriers capable of precisely targeting infection sites, followed by responding to the different microenvironments of infectious sites, enabling controlled drug release on demand. These smart delivering systems significantly enhance the delivery efficacy of drugs to infection sites, reduce systemic toxicity, and improve treatment efficacy [64, 67]. Additionally, imidazolium-based coatings on medical implants, such as orthopedic devices and vascular grafts, effectively prevented biofilm formation, significantly reducing the risk of device-associated infections in clinical settings [68–70].
1.2.3.2.2 Environmental and Industrial Applications
In environmental applications, imidazolium-based polymers have shown promise in water and wastewater treatment (see Figure 1.4a). For example, highly stable imidazolium-based ionic porous organic polymers were prepared by the condensation reaction between imidazole with Tris-(4-bromomethyl-phenyl)-[1,3,5]triazine. The as-made polymers were characterized by nitrogen-rich triazine core and imidazole derivatives, bearing exchangeable bromide anions inside the porous networks. The polymers showed highly selective and efficient capture of toxic and hazardous (170 mg g−1) and (515.5 mg g−1) anions from wastewater. In addition, this showed reusability up to three cycles for the oxo-anions, advocating as potential candidates for real-time utilization in such oxo-anion sequestration applications. These polymers have also been used as antifouling coatings for oil/water separation in the industrial field. Besides, poly-imidazolium-based hydrogel-coated stainless steel mesh with super-hydrophilicity and underwater super-oleophobicity was constructed via cross-linking chitosan with a poly-imidazolium chain. The as-prepared 3D hydrogel network demonstrated outstanding stability and endurance under harsh conditions such as acidic, alkaline, and salty environments. Moreover, they presented high water flux and oil separation efficiency (>99.5%) as well as superb antibacterial efficacy (99.999%) and anti-biofouling activity against both Gram-positive and Gram-negative bacteria [71].
