Nanoparticle Doped PEDOT for Enhanced Electrode Coatings and Drug Delivery

Abstract

In order to address material limitations of biologically interfacing electrodes, modified silica nanoparticles are utilized as dopants for conducting polymers. Silica precursors are selected to form a thiol modified particle (TNP), following which the particles are oxidized to sulfonate modified nanoparticles (SNPs). The selective inclusion of hexadecyl trimethylammonium bromide allows for synthesis of both porous and nonporous SNPs. Nonporous nanoparticle doped polyethylenedioxythiophene (PEDOT) films possess low interfacial impedance, high charge injection (4.8 mC cm−2), and improved stability under stimulation compared to PEDOT/poly(styrenesulfonate). Porous SNP dopants can serve as drug reservoirs and greatly enhance the capability of conducting polymer‐based, electrically controlled drug release technology. Using the SNP dopants, drug loading and release is increased up to 16.8 times, in addition to greatly expanding the range of drug candidates to include both cationic and electroactive compounds, all while maintaining their bioactivity. Finally, the PEDOT/SNP composite is capable of precisely modulating neural activity in vivo by timed release of a glutamate receptor antagonist from coated microelectrode sites. Together, this work demonstrates the feasibility and potential of doping conducting polymers with engineered nanoparticles, creating countless options to produce composite materials for enhanced electrical stimulation, neural recording, chemical sensing, and on demand drug delivery.

Nanomaterial‐Based Electrochemical Sensors: Mechanism, Preparation, and Application in Biomedicine

“…[ 93 ] In 2018, they further extended the targeted drug to Levodopa, i.e., a treatment for Parkinson's disease. [ 94 ] Specifically, gold nanodendrites with large surface areas were synthesized via an overpotential deposition approach on the evaporated Au/Cr conductive layer, offering adequate interfaces for enzyme loading and molecular sensing. The performance of prolonged, continuous, and noninvasive drug monitoring in human subjects enabled dosage optimization in a point‐of‐care and precise manner.…”

“…[ 100 ] Woeppel et al precisely controlled the drug release from the sulfonated silica NP‐doped composite by electrochemical method ( Figure 6 A). [ 94 ] In this article, SiO 2 NP dopants not only provided a potential drug delivery library but also maintained favorable electrochemical properties. Controlled release of DOX within a few seconds were achieved by the electron injection into doxorubicin (DOX)@nanographene oxide/platinum micromachines, with the reduced nanographene oxide serving as a drug‐loading platform.…”

“…Reproduced with permission. [ 94 ] Copyright 2019, Wiley‐VCH. B) A graphene‐mixed array with skin‐fitting property for diabetic monitoring and treatment.…”

Wirelessly triggered bioactive molecule delivery from degradable electroactive polymer films

“…inflammation and scar tissue formation around the metal–tissue interface) that motivates the development of softer non‐degradable conductive coatings (e.g. conductive polymers), 32–39 potentially using microscale/nanoscale patterns to instruct cell behaviour, 40,41 or indeed capable of delivering bioactive substances from the electrode coating (e.g. anti‐inflammatories such as dexamethasone phosphate (DMP) and antimicrobials) 42 …”

Conducting Polymer-Based Composite Materials for Therapeutic Implantations: From Advanced Drug Delivery System to Minimally Invasive Electronics

“…In this study, 0.5 μg/cm 2 dexamethasone can be released after each CV cycle and up to a total of nearly 16 μg/cm 2 can be released after 30 CV cycles ( Figure 1(d)). To further enhance the drug release performance and drug-loading capacity of the ICPs, Woeppel et al reported the usage of functionalized negatively charged porous silica nanoparticles as the dopant for PEDOT [46]. The silica nanoparticle-doped PEDOT showed significantly enhanced doxorubicin (DOX) release profiles (up to 7-folds higher than the control) by applying electrical stimulations; different kinds of drugs, e.g., fluorescein and DNQX, have been loaded into the porous silica nanoparticle-doped PEDOT and demonstrated controllable release profiles in vivo.…”