Brush Grafting Research Articles

Rapid Construction of Liquid-like Surfaces via Single-Cycle Polymer Brush Grafting for Enhanced Antifouling in Microfluidic Systems.

Liquid-like surfaces have demonstrated immense potential in their ability to resist cell adhesion, a critical requirement for numerous applications across various domains. However, the conventional methodologies for preparing liquid-like surfaces often entail a complex multi-step polymer brush modification process, which is not only time-consuming but also presents significant challenges. In this work, we developed a single-cycle polymer brush modification strategy to build liquid-like surfaces by leveraging high-molecular-weight bis(3-aminopropyl)-terminated polydimethylsiloxane, which significantly simplifies the preparation process. The resultant liquid-like surface is endowed with exceptional slipperiness, effectively inhibiting bacterial colonization and diminishing the adherence of platelets. Moreover, it offers promising implications for reducing the dependency on anticoagulants in microfluidic systems constructed from PDMS, all while sustaining its antithrombotic attributes.

XPS Depth-Profiling Studies of Chlorophyll Binding to Poly(cysteine methacrylate) Scaffolds in Pigment-Polymer Antenna Complexes Using a Gas Cluster Ion Source.

X-ray photoelectron spectroscopy (XPS) depth-profiling with an argon gas cluster ion source (GCIS) was used to characterize the spatial distribution of chlorophyll a (Chl) within a poly(cysteine methacrylate) (PCysMA) brush grown by surface-initiated atom-transfer radical polymerization (ATRP) from a planar surface. The organization of Chl is controlled by adjusting the brush grafting density and polymerization time. For dense brushes, the C, N, S elemental composition remains constant throughout the 36 nm brush layer until the underlying gold substrate is approached. However, for either reduced density brushes (mean thickness ∼20 nm) or mushrooms grown with reduced grafting densities (mean thickness 6-9 nm), elemental intensities decrease continuously throughout the brush layer, because photoelectrons are less strongly attenuated for such systems. For all brushes, the fraction of positively charged nitrogen atoms (N+/N0) decreases with increasing depth. Chl binding causes a marked reduction in N+/N0 within the brushes and produces a new feature at 398.1 eV in the N1s core-line spectrum assigned to tetrapyrrole ring nitrogen atoms coordinated to Zn2+. For all grafting densities, the N/S atomic ratio remains approximately constant as a function of brush depth, which indicates a uniform distribution of Chl throughout the brush layer. However, a larger fraction of repeat units bound to Chl is observed at lower grafting densities, reflecting a progressive reduction in steric congestion that enables more uniform distribution of the bulky Chl units throughout the brush layer. In summary, XPS depth-profiling using a GCIS is a powerful tool for characterization of these complex materials.

Hybrid Bonding Bottlebrush Polymers Grafted from a Supramolecular Polymer Backbone.

Bottlebrush polymers, macromolecules consisting of dense polymer side chains grafted from a central polymer backbone, have unique properties resulting from this well-defined molecular architecture. With the advent of controlled radical polymerization techniques, access to these architectures has become more readily available. However, synthetic challenges remain, including the need for intermediate purification, the use of toxic solvents, and challenges with achieving long bottlebrush architectures due to backbone entanglements. Herein, we report hybrid bonding bottlebrush polymers (systems integrating covalent and noncovalent bonding of structural units) consisting of poly(sodium 4-styrenesulfonate) (p(NaSS)) brushes grafted from a peptide amphiphile (PA) supramolecular polymer backbone. This was achieved using photoinitiated electron/energy transfer-reversible addition-fragmentation chain transfer (PET-RAFT) polymerization in water. The structure of the hybrid bonding bottlebrush architecture was characterized using cryogenic transmission electron microscopy, and its properties were probed using rheological measurements. We observed that hybrid bonding bottlebrush polymers were able to organize into block architectures containing domains with high brush grafting density and others with no observable brushes. This finding is possibly a result of dynamic behavior unique to supramolecular polymer backbones, enabling molecular exchange or translational diffusion of monomers along the length of the assemblies. The hybrid bottlebrush polymers exhibited higher solution viscosity at moderate shear, protected supramolecular polymer backbones from disassembly at high shear, and supported self-healing capabilities, depending on grafting densities. Our results demonstrate an opportunity for novel properties in easily synthesized bottlebrush polymer architectures built with supramolecular polymers that might be useful in biomedical applications or for aqueous lubrication.

Fabrication of a scalable slippery surface via novel sprayable breath figure technique for sustainable drag reduction and anti-biofouling in marine environments

The maritime industry has been seeking efficient solutions to combat hydrodynamic friction and biofouling, which increase operational costs and environmental issues. To address these concerns, we developed a novel sprayable breath figure (sBF) method to create a scalable and cost-effective lubricant-infused surface (LIS) for reducing frictional drag forces on marine vehicles. The proposed sBF method facilitated the rapid production of multilayered porous polymer films with micron-scale spherical cavities. It can be applied to large and curved surfaces, thus overcoming the limitations of traditional breath figure methods. Further surface treatment of oxygen plasma etching followed by polydimethylsiloxane (PDMS) brush grafting was employed to optimize the interfacial slip and lubricant retention of the slippery surface coating. The PDMS brush-grafted slippery surfaces demonstrated significant drag reduction under turbulent flow conditions. This was confirmed by direct velocity field measurements, showing nonzero slip velocity unlike conventional no-slip surfaces. The same surfaces also exhibited remarkable anti-biofouling performance, severely resisting marine biofouling in real-sea field tests over 50 days. The proposed sBF method was successfully applied to large-area and curved submerged bodies, and achieved a noticeable drag reduction under high-speed turbulent flows. This study is a critical step toward the practical implementation of this technology in the marine industry.

Design of hydrophobic polymer brush for mitigation of membrane wetting in membrane distillation- computer simulation

Defined as an assembly of polymer chains which are tethered by one end to a surface or an interface, polymer brushes have found many applications. In particular, grafting of hydrophilic polymer brushes to the membrane surface was used to mitigate fouling of filtration membranes. As well, hydrophobic polymer brushes were grafted on top of a solid substrate to be used for organic selective pervaporation. In this work, grafting of hydrophobic brushes to the surface of membranes for membrane distillation (MD) is proposed to prevent MD membranes from wetting. This is not an experimental work but a computer simulation of designing the polymer brush or patterned polymer brush to optimize their effect on wetting prevention. It was found that such an effect increases with an increase in the distance between brushes, the contact angle and the radius of the cylindrical polymer brush. Considering the decrease in the effective area of the membrane used for vapor permeation by grafting of polymer brush, the optimal distance between the brushes was found to be twice as large as the brush diameter for millimeter-sized brush and three times as large as the brush diameter of micro- or nanometer sized brushes.

Construction of antithrombotic and antimicrobial ultra-thin structures on a polyethylene terephthalate implant via the surface grafting of heparin brushes.

It remains a challenge to endow a polymeric material with antithrombotic ability by surface grafting without disturbing the bulk properties of the substrate. Heparin-based functional structures of less than 80 nm were fabricated and covalently grafted on a polyethylene terephthalate surface via carbene chemistry (Hep-g-PET). Heparin was oxidized with the minimum antithrombrin sequence retained, creating an aldehyde group on the chain terminus. Oxidized heparin was then covalently attached to a poly(amidoamine) (PAMAM)-grafted PET substrate. The interface between blood and PET was improved by the surface functionality, and the amount of attached platelets decreased to 29 ± 12.1% of its initial value. The bulk properties of the functionalized film were hardly influenced, and the visible light transmittance remained more than 96%. The tethered structures also showed the ability to kill attached S. aureus and E. coli efficiently. The functionalized membrane showed negligible ex vivo cell cytotoxicity and a low hemolysis ratio. Hep-g-PET was implanted in between rat skin and muscle, and showed an outstanding histological response and antimicrobial ability. The influences of the graft thickness and the heparin chain length were explored. The strategies reported in this work may help to improve the design of polymeric implant bio-devices.

A surface grafting strategy for antifouling/bioadhesive properties on a Janus-type polymeric thin film

There have been great technical challenges in preparation of a transparent polymeric thin film with Janus-type antifouling and bioadhesive properties on both surfaces, while maintaining the optical and mechanical characteristics of the bulk material. Herein, poly(2-hydroxyethyl methacrylate) (PHEMA), which is commonly used as an ophthalmic hydrogel, was employed as the bulk material for allowing consecutive surface grafting of functional polymer brushes, which eventually resulted in a Janus-type transparent thin film for potential biomedical implantation. First, a bromine-containing reagent served as the reactive initiator was silanized onto both surfaces of the PHEMA hydrogel thin film under a mild condition. Then, with the presence of selected physical shielding on one side using a scotch tape, polymer brushes with cell-adhesive Arg-Gly-Asp (RGD) peptide pendent groups were grafted from the other side of the PHEMA thin film, resulted in a highly improved cell attachment capability. Once the tape was removed and the RGD-modified surface was shielded, the zwitterionic polymer brushes comprising poly(2-methacryloyloxyethyl phosphorylcholine) (PMPC) segments were grafted on the surface, again through surface-initiated activators regenerated by electron transfer atom-transfer radical polymerization (SI-ARGET-ATRP). Hence, this side of the PHEMA film became super hydrophilic and exhibited antifouling properties on the surface. After the surface grafting modification, the whole PHEMA hydrogel maintained highly transparent and biocompatible for potential ophthalmic applications. This study provides a simple and rather universal strategy for fabricating Janus-type polymeric thin films with distinct biophysical/biochemical properties on both sides, which potentially applicable for the multifunctional requirements in biomedical applications.

Lubricant-infused anodic aluminum oxide surface (AAO-LIS) for durable slipperiness under harsh conditions

The wettability of surfaces plays a crucial role in determining their applications, and slippery surfaces have been utilized in various fields. Especially, lubricant-infused surface (LIS) has been undergone extensive research over the past decade. However, LIS tends to lose its infused lubricant and consequently lose its slippery properties when exposed to harsh conditions. Therefore, there is a strong need to enhance the durability of the infused lubricant. Herein, two strategies are adopted to improve the durability of slippery properties against centrifugal forces and high-speed shear flows. One strategy is using re-entrant shaped nanocavities, and the other is grafting PDMS brush onto the surface. Anodic aluminum oxide (AAO) is employed to fabricate the re-entrant shaped nanocavities, and the durability of the infused lubricant is improved when the cavities have a smaller diameter. Furthermore, the re-entrant shape of nanocavity significantly improves the durability compared to nanocavity with a constant diameter. The grafting of PDMS brush is essential for enhancing the durability, and an increase in the length of the PDMS brush also improves the durability. The fabricated AAO-based LIS (AAO-LIS) maintains the slippery properties for 50 min under a high-speed water flow of 12 m/s. In addition, it maintains its superior slipperiness for more than a few days when exposed to actual seawater. Furthermore, the frictional drag reduction performance of the fabricated AAO-LIS is assessed. The proposed AAO-LIS maintains a certain drag reduction performance durably even after losing its superior slipperiness, demonstrating its strong potential for practical applications across various industrial fields.

Surface-Initiated PET-RAFT via the Z-Group Approach.

Surface-initiated reversible addition-fragmentation chain transfer (SI-RAFT) is a user-friendly and versatile approach for polymer brush engineering. For SI-RAFT, synthetic strategies follow either surface-anchoring of radical initiators (e.g., azo compounds) or anchoring RAFT chain transfer agents (CTAs) onto a substrate. The latter can be performed via the R-group or Z-group of the CTA, with the previous scientific focus in literature skewed heavily toward work on the R-group approach. This contribution investigates the alternative: a Z-group approach toward light-mediated SI photoinduced electron transfer RAFT (SI-PET-RAFT) polymerization. An appropriate RAFT CTA is synthesized, immobilized onto SiO2, and its ability to control the growth (and chain extension) of polymer brushes in both organic and aqueous environments is investigated with different acrylamide and methacrylate monomers. O2 tolerance allows Z-group SI-PET-RAFT to be performed under ambient conditions, and patterning surfaces through photolithography is illustrated. Polymer brushes are characterized via X-ray photoelectron spectroscopy (XPS), ellipsometry, and water contact angle measurements. An examination of polymer brush grafting density showed variation from 0.01 to 0.16 chains nm-2. Notably, in contrast to the R-group SI-RAFT approach, this chemical approach allows the growth of intermittent layers of polymer brushes underneath the top layer without changing the properties of the outermost surface.

Scalable Zwitterionic Polymer Brushes for Antifouling Membranes via Cu0-Mediated Atom Transfer Radical Polymerization

Polymer brush layers have attracted significant interest for versatile, controlled surface modification enabling fabrication and functionalization of membranes for water treatment and reuse applications. In particular, zwitterionic polymer brushes have been shown to provide strong resistance to organic fouling, oil fouling, biofouling, and inorganic fouling as membrane coatings for a variety of membrane processes. However, despite the demonstrated performance of polymer brush membranes, there are significant challenges associated with commercial scale-up of traditional fabrication methods. In this work, we demonstrate scalable grafting of zwitterionic polymer brushes from microfiltration membrane substrates under ambient conditions, and with low chemical consumption, for the first time, via Cu0-mediated surface-initiated atom transfer radical polymerization (Cu0-SI-ATRP). We demonstrate that Cu0-SI-ATRP is effective for brush grafting from porous membrane substrates, including samples of up to 150 cm2. Furthermore, we systematically investigate the effect of polymerization in confinement on brush growth kinetics and fouling resistance, using colloid probe force microscopy and dynamic fouling experiments. Results demonstrate that Cu0-SI-ATRP results in poly(sulfobetaine methacrylate) brush layers that significantly improve fouling resistance; however, polymerization methods significantly impact fouling resistance, for both Si wafer and membrane substrates. We identify polymerization methods that enhance fouling resistance even for thin brush layers. The results of this study provide pathways to the scalable fabrication and design of robust, antifouling membranes for applications in water treatment, water reuse, and resource recovery from waste streams.

High performance polyvinylidene fluoride membrane functionalized with poly(ionic liquid) brushes for dual resistance to organic and biological fouling

The balance between antifouling properties and permeability is an inevitable problem for the application of ultrafiltration membranes. Herein, hydrophilic poly(ionic liquid) (PIL)-functionalized PVDF membranes with organic foulant resistance and bacterial killing properties were developed via atom transfer radical polymerization (ATRP). PILs with different anions bromide ([Br]-), tetrafluoroborate ([BF4]-) and hexafluorophosphate ([PF6]-) were functionalized onto the membrane surface, which all showed microbial inactivation ability. By optimizing PIL anions and ATRP conditions, a C4BF4-M membrane with favorable antibacterial and hydrophilic surface properties was obtained, which showed dual resistance to organic and biological fouling. With bovine serum albumin (BSA) and E. coli as model foulants, dynamic filtration tests further confirmed that PIL-M membranes have favorable anti-organic and anti-biological fouling abilities. Compared with the pristine PVDF membrane, the stable water flux of the C4BF4-M membrane increased up to 56% and 32%, respectively, during the anti-organic and anti-biological fouling experiments. The surface plasmon resonance confirmed that very loose binding can be formed between BSA and PIL brushes, leading to the excellent anti-organic fouling performance of the C4BF4-M membrane. We further evaluated the practical application and substantially reduced the fouling potential of the PIL-M membrane by wastewater effluent filtration tests. The results confirm that the surface grafting of PIL brushes is a promising method for membrane fouling control.

Sticky Architecture: Encoding Pressure Sensitive Adhesion in Polymer Networks.

Pressure sensitive adhesives (PSAs) are ubiquitous materials within a spectrum that span from office supplies to biomedical devices. Currently, the ability of PSAs to meet the needs of these diverse applications relies on trial-and-error mixing of assorted chemicals and polymers, which inherently entails property imprecision and variance over time due to component migration and leaching. Herein, we develop a precise additive-free PSA design platform that predictably leverages polymer network architecture to empower comprehensive control over adhesive performance. Utilizing the chemical universality of brush-like elastomers, we encode work of adhesion ranging 5 orders of magnitude with a single polymer chemistry by coordinating brush architectural parameters-side chain length and grafting density. Lessons from this design-by-architecture approach are essential for future implementation of AI machinery in molecular engineering of both cured and thermoplastic PSAs incorporated into everyday use.

Controlled Orientation of Silicon-Containing Diblock Copolymer Thin Films by Substrate Functionalization Under Vacuum

This work demonstrates a simple approach to control the orientation of the self-assembled nanostructured block copolymer thin films of polystyrene-block-polydimethylsiloxane (PS-b-PDMS) by functionalization of the oxide layer (SiO2) on the Si substrate followed by thermal annealing under low-pressure environmental conditions. The substrate can be functionalized through two-step grafting of hydroxy-terminated polystyrene brush (PS–OH brush) followed by hydroxy-terminated polydimethylsiloxane brush (PDMS–OH brush) onto the wafer substrate. By controlling the grafting ratio of PS–OH and PDMS–OH brushes, the affinities of the PS and PDMS blocks with the substrates can be fine-tuned to provide a neutral substrate in order to form perpendicular cylinders from the bottom after thermal annealing. Owing to the vacuum-driven orientation [i.e., thermal annealing under low-pressure environment conditions (∼10–4 Pa)], the orientation of the cylinders can be controlled at the air/polymer interface. Interestingly, by combining the vacuum-driven approach with substrate functionalization, perpendicular cylinders from the air/polymer interface and substrate/polymer interface can be generated, respectively. Consequently, well-aligned perpendicular cylinders with long-range ordering can be fabricated by the self-alignment process.

Shear-Stable Polymer Brush Surfaces.

Research on polymer brushes (PBs) has aroused great interest due to their wide range of applications in lubrication, antifogging, antifouling, self-cleaning, antiadhesion, antibacterial effects, and so forth. However, the weak mechanical strength, especially the low bond strength between the PBs and the substrate surface, is a long-standing challenge for its practical applications, which is directly related to the service life of the PB surface. Fortunately, the imperfection of the PB surface was gradually solved by researchers by combining the action of the chemical and physical anchoring strength, and many shear-stable PB surfaces were developed. In this Perspective, we present recent developments in the studies of shear-stable PBs. Conventional strategies that altered the structure of PB chain methods, including increasing grafted density, cross-linking of PBs, cyclic PBs, and so forth, are introduced briefly. The systematic subsurface grafting of the polymer brush (SSPB) strategy was introduced emphatically. The SSPB method grafted PB into the subsurface with considerable depth and gave a robust and reusable PB layer, which provided an approach for tackling the shear-resistance issue. Besides, the robust hydrophobic poly(dimethylsiloxane) (PDMS) brush surface that lubricated itself in air was also introduced. Finally, we provide a synopsis and discuss the outlook of the shear-stable PB surface.

Sequential Brush Grafting for Chemically and Dimensionally Tolerant Directed Self-Assembly of Block Copolymers

We report a method for the directed self-assembly (DSA) of block copolymers (BCPs) in which a first BCP film deploys homopolymer brushes, or "inks", that sequentially graft onto the substrate's surface via the interpenetration of polymer molecules during the thermal annealing of the polymer film on top of existing polymer brushes. By selecting polymer "inks" with the desired chemistry and appropriate relative molecular weights, it is possible to use brush interpenetration as a powerful technique to generate self-registered chemical contrast patterns at the same frequency as that of the domains of the BCP. The result is a process with a higher tolerance to dimensional and chemical imperfections in the guiding patterns, which we showcase by implementing DSA using homopolymer brushes for the guiding features as opposed to more robust cross-linkable mats. We find that the use of "inks" does not compromise the line width roughness, and the quality of the DSA as a lithographic mask is verified by implementing a robust "dry lift-off" pattern transfer.

Facile optimization of grafted chain length on antifouling properties based on hyperbranched polyglycerol

Surface-grafted polymer brushes for enhancing biofouling resistance are determined by both the grafting density and chain length of brush on the antifouling membrane surfaces. However, the relations and internal regularities between the arrangement of polymer brush and the permeability and antifouling properties remain unsolved. The accurate effect of chain length is lost on the biofouling resistance behaviors. Herein, antifouling membrane surfaces of hyperbranched polyglycerol (HPG) brushes are obtained via tuning the chain lengths of HPG brush. The wettability and proteins' static adsorption are dramatically improved with the increase of HPG chain lengths. The parameter of chain volume overlap is preliminarily involved to describe the spatial distribution of HPG brushes. Unexpectedly, we demonstrate that the chain length of HPG is critical and a medium-length HPG brush displays an emerging permeability by a dense enough chain volume overlap (Dv) of the HPG architecture. The biofouling resistance behaviors are optimized using the response surface methodology. As the HPG brush grafting density increased, a higher flux recovery regardless of the chain lengths is observed. Qualitative and quantitative assays of E. coli and S. aureus attachment further reveal the low fouling characteristics of hyperbranched membrane surfaces. A deeper understanding of how the chain length of polymer brushes impacts permeability and the anti-biofouling property provides general guidance on the effectiveness of grafted polymer brushes.

Preparation of polyethylene glycol brush grafted from the surface of nitrile butadiene rubber with excellent tribological performance under aqueous lubrication

The water-lubricated bearing will be in a state of poor lubrication when marine stern shafts operate under low speed and heavy load conditions, which could cause severe wear and vibration, endangering the stealth performance of underwater vehicles. In this study, the grafting of polyethylene glycol brush was carried out on the surface of nitrile butadiene rubber (PEG-g-sNBR) by “grafting from” method. Fourier-transform-infrared-spectroscopy, nuclear-magnetic-resonance, and scanning-electron- microscope results demonstrated that the PEG-g-sNBR brush was successfully synthesized, and the reactive site was found. Using a tribological test machine with a high-precision vibration acceleration sensor, the tribological behaviors of PEG-g-sNBR were studied under aqueous lubrication. The results showed that the coefficient of friction of PEG-g-sNBR was reduced by 73.4% at 100 rpm compared to pure NBR, its microscopic wear and vibrational energy were also lower than pure NBR. Moreover, the lubrication states were revealed by friction, wear, together with the complexity of friction-induced vibration signal time series, and a lubricating film was formed on the friction surface of PEG-g-sNBR at lower rotational speed. In addition, the PEG-g-sNBR could work stably for 12 h at 300 rpm, and still maintain good tribological performance.

Advances in design of polymer brush functionalized inorganic nanomaterials and their applications in biomedical arena.

Grafting of polymer brush (assembly of polymer chains tethered to the substrate by one end) is emerging as one of the most viable approach to alter the surface of inorganic nanomaterials. Inorganic nanomaterials despite their intrinsic functional superiority, their applications remain restricted due to their incompatibility with organic or biological moieties vis-à-vis agglomeration issues. To overcome such a shortcoming, polymer brush modified surfaces of inorganic nanomaterials have lately proved to be of immense potential. For example, polymer brush-modified inorganic nanomaterials can act as efficient substrates/platforms in biomedical applications, ranging from drug-delivery to protein-array due to their integrated advantages such as amphiphilicity, stimuli responsiveness, enhanced biocompatibility, and so on. In this review, the current state of the art related to polymer brush-modified inorganic nanomaterials focusing, not only, on their synthetic strategies and applications in biomedical field but also the architectural influence of polymer brushes on the responsiveness properties of modified nanomaterials have comprehensively been discussed and its associated future perspective is also presented. This article is categorized under: Diagnostic Tools > In Vivo Nanodiagnostics and Imaging Therapeutic Approaches and Drug Discovery > Emerging Technologies Nanotechnology Approaches to Biology > Nanoscale Systems in Biology.

Fabrication of polyelectrolyte brush-functionalized two-dimensional covalent organic frameworks as additives for aqueous lubricants

A polyelectrolyte brush-functionalized COF nanosheets exhibiting fine dispersion stability in water were successfully prepared via UV-induced thiol-ene “click” reaction for initiator binding and subsequent surface-initiated ATRP for polyelectrolyte brush grafting. The as-prepared TD-COF-PSPMA, as water-based lubricant additive, appears as an effective agent to reduce friction and wear; the average friction coefficient of the lubricant decreases to 0.173 from 0.596 under 5 N and 0.5 wt% addition concentration. The advantage of TD-COF-PSPMA is the efficient adsorption of anion groups to the positively charged iron surface, which is beneficial to the formation of a tribo-chemical protective film over the worn surface. Moreover, the presence of hydration layer confined with polyelectrolyte brushes is conducive to friction reduction, resulting in the remarkable lubrication performance.

Zwitterionic Conducting Polymers: From Molecular Design, Surface Modification, and Interfacial Phenomenon to Biomedical Applications.

Conducting polymers (CPs) have gained attention as electrode materials in bioengineering mainly because of their mechanical softness compared to conventional inorganic materials. To achieve better performance and broaden bioelectronics applications, the surface modification of soft zwitterionic polymers with antifouling properties represents a facile approach to preventing unwanted nonspecific protein adsorption and improving biocompatibility. This feature article emphasizes the antifouling properties of zwitterionic CPs, accompanied by their molecular synthesis and surface modification methods and an analysis of the interfacial phenomenon. Herein, commonly used methods for zwitterionic functionalization on CPs are introduced, including the synthesis of zwitterionic moieties on CP molecules and postsurface modification, such as the grafting of zwitterionic polymer brushes. To analyze the chain conformation, the structure of bound water in the vicinity of zwitterionic CPs and biomolecule behavior, such as protein adsorption or cell adhesion, provide critical insights into the antifouling properties. Integrating these characterization techniques offers general guidelines and paves the way for designing new zwitterionic CPs for advanced biomedical applications. Recent advances in newly designed zwitterionic CP-based electrodes have demonstrated outstanding potential in modern biomedical applications.