Conductive, Injectable, and Spinnable Aniline Tetramer-Modified Polysaccharide Hydrogels for Self-Powered Electrically Responsive Drug Release

Self-powered electrically responsive and wearable/implantable drug delivery based on conductive, injectable, and biocompatible hydrogels has emerged as a paradigm for on-demand treatment of diseases. Herein, an electroactive aniline tetramer (AT)-grafted mushroom hyperbranched polysaccharide (TM3a) was codissolved with xanthan gum (XG) and cross-linked with sodium trimetaphosphate (STMP) to fabricate conductive and injectable XG-TMAT-STMP hydrogels. The XG3-TMAT30-STMP hydrogel swollen in a simulated gastric fluid possessed a high conductivity of 23.27 +/- 0.20 mS/cm. When applying a potential of 3 V, the apparent diffusion coefficient increased regardless of whether placing DXMS-loaded hydrogels between two electrodes or setting them at the anode or the cathode, indicating electrically responsive release. The extruded XG3-TMATSTMP hydrogel fibers exhibited good conductivity and stretchablility with low a gauge factor of 1.13 (10% < epsilon < 50%), suggesting potential applications as bioelectrodes and wearable/implantable drug carriers. Additionally, a triboelectric nanogenerator was fabricated by applying the XG3-TMAT30-STMP hydrogel as a triboelectric material to harvest an output potential of 0.9-1.3 V, indicating feasible application as a self-powered source.