Combinatorial Polyacrylamide Hydrogels for Preventing Biofouling on Implantable Biosensors

Abstract

Biofouling on the surface of implanted medical devices and biosensors severely hinders device functionality and drastically shortens device lifetime. Poly(ethylene glycol) and zwitterionic polymers are currently considered “gold‐standard” device coatings to reduce biofouling. To discover novel anti‐biofouling materials, a combinatorial library of polyacrylamide‐based copolymer hydrogels is created, and their ability is screened to prevent fouling from serum and platelet‐rich plasma in a high‐throughput parallel assay. It is found that certain nonintuitive copolymer compositions exhibit superior anti‐biofouling properties over current gold‐standard materials, and machine learning is used to identify key molecular features underpinning their performance. For validation, the surfaces of electrochemical biosensors are coated with hydrogels and their anti‐biofouling performance in vitro and in vivo in rodent models is evaluated. The copolymer hydrogels preserve device function and enable continuous measurements of a small‐molecule drug in vivo better than gold‐standard coatings. The novel methodology described enables the discovery of anti‐biofouling materials that can extend the lifetime of real‐time in vivo sensing devices.

Mucosa-interfacing electronics

“…Additionally, biofouling of sensors and device components, which leads to signal drift or loss of functionality, is a particular concern in mucosal environments, which regularly encounter exogenous debris 128 . Beyond the poly(ethylene glycol) and zwitterionic coatings commonly used to reduce biofouling, combinatorial screening approaches have also yielded promising candidates for coating implantable biosensors, including certain copolymers with acrylamide, which could be used in the future to address biofouling in different mucosal environments 129 .…”

Construction of hydrogel composites with superior proton conduction and flexibility using a new POM-based inorganic–organic hybrid

“…Hydrogels are flexible materials with crosslinked polymer networks capable of holding a great deal of water [19,20]. Recently, ionic conductive hydrogels have attracted much attention as solid electrolytes with promising application potential in wearable electronics [21][22][23], biosensors [24][25][26], and flexible energy storage devices [27][28][29] due to their outstanding flexibility, conductivity, and biocompatibility. POMs have been used as conductive inorganic fillers to create ionic conductive hydrogels with hydrophilic polymers [30].…”

Uncovering the Sweat Biofouling Components and Distributions in Electrochemical Sensors

“…Despite the abundant attractive merits of wearable sweat sensors presented, the ubiquitous challenges of the biofouling phenomenon limit the continuity of sensors, hence placing restrictions on their further application, popularization, and commercialization . Biofouling is a very common issue in electrochemical biosensing and for the sensing of blood and tissue fluid; sensor fouling is attributed to the nonspecific protein adsorption and undesired cell adhesion inducing electrode passivation . For other complex biofluids such as serum and interstitial fluid, it is mainly the adsorption of proteins to the electrode surface that hinders the approaching of targets toward the electrode surface and leads to biofouling .…”

“…12 Biofouling is a very common issue in electrochemical biosensing and for the sensing of blood and tissue fluid; sensor fouling is attributed to the nonspecific protein adsorption and undesired cell adhesion inducing electrode passivation. 13 For other complex biofluids such as serum and interstitial fluid, it is mainly the adsorption of proteins to the electrode surface that hinders the approaching of targets toward the electrode surface and leads to biofouling. 14 The sensor performance gradually degrades over time with accumulation of sample biomolecule adsorption, diminishing both the electrochemical signal magnitude and specificity of the biosensor, all of which can substantially contribute to device failure.…”