Mussel-Inspired Redox-Active and Hydrophilic Conductive Polymer Nanoparticles for Adhesive Hydrogel Bioelectronics

Abstract

Conductive polymers (CPs) are generally insoluble, and developing hydrophilic CPs is significant to broaden the applications of CPs. In this work, a mussel-inspired strategy was proposed to construct hydrophilic CP nanoparticles (CP NPs), while endowing the CP NPs with redox activity and biocompatibility. This is a universal strategy applicable for a series of CPs, including polyaniline, polypyrrole, and poly(3,4-ethylenedioxythiophene). The catechol/quinone contained sulfonated lignin (LS) was doped into various CPs to form CP/LS NPs with hydrophilicity, conductivity, and redox activity. These CP/LS NPs were used as versatile nanofillers to prepare the conductive hydrogels with long-term adhesiveness. The CP/LS NPs-incorporated hydrogels have a good conductivity because of the uniform distribution of the hydrophilic NPs in the hydrogel network, forming a well-connected electric path. The hydrogel exhibits long-term adhesiveness, which is attributed to the mussel-inspired dynamic redox balance of catechol/quinone groups on the CP/LS NPs. This conductive and adhesive hydrogel shows good electroactivity and biocompatibility and therefore has broad applications in electrostimulation of tissue regeneration and implantable bioelectronics.

Recent progress in polymer hydrogel bioadhesives

“…In contrast to conventional adhesives, hydrogel adhesives are flexible for chemical design, mechanical properties, and processibility for wound closure and tissue regeneration. Hydrogel adhesives have great potentials in clinical applications, 5–8 implantable devices 9,10 and electronic skin 11–13 …”

A Novel Dual‐Crosslinked Functional Hydrogel Activated by POSS for Accelerating Wound Healing

“…In the POSSP spectrum, the protons in the catechol ring newly appeared at 6.72 ppm, and the proton peak at 2.83 ppm was owing to a CH 2  group close to the catechol ring. [ 28,29 ] Successful conjugation of dopamine to POSS–Ac was achieved. The distribution and particle sizes of the synthetic nanoparticles were confirmed by TEM.…”

Soft materials for wearable supercapacitors

“…Heretofore, the development of soft materials for supercapacitors that can be deformed into arbitrary shapes and adapt to random musculoskeletal deformations in the human body is still a considerable challenge. [231][232][233][234][235] which could be further applied as soft electrodes for WSCs. In these previous studies, polydopamine (PDA) was combined with the hydrogels, which endows the hydrogels with good shef-adhesivness that inspired by mussel [236].…”