노화인자 자극반응형 탄소소재-하이드로젤 기반 무선 진단 및 치료기술 = Aging-Related Disease Biomarker Responsive Polymer Dots Incorporated Touchable Electrochemical Hydrogel for Wireless Sensing and Therapy

다국어 초록 (Multilingual Abstract)

Aging-related diseases such as Alzheimer’s and osteoarthritis are characterized by the presence of elevated cholinergic enzyme acetylcholineesterase (AChE) and overexpressed reactive oxygen species (ROS). These overexpressed biomarkers cause damage to nervous synapses in the autonomic nervous system responsible for movement and cause progression of degeneration of joints and other body parts. Herein, we designed stimuli-responsive electrochemical hydrogel sensors by coupling polymer dots with hydrogel matrices for targeting acetylcholinesterase in Alzheimer's disease and reactive oxygen species in osteoarthritis. For Alzheimer’s disease, we synthesized an AChE-responsive, dual-mode (fluorescent and electrochemical) biosensor by loading acetylthiocholine (ATCh) and a diselenide- crosslinked polymer dot-polydopamine complex (PDA@dsPD) into the hydrogel matrix. When AChE hydrolyzed ATCh to thiocholine (TCh), TCh cleaved diselenide bonds, leading to fluorescence dequenching and impedance modulation, which enabled sensitive readout of both AChE activity and its inhibition. For aging-related diagnosis, we fabricated a ROS-responsive (PD/MnO₂) hydrogel, in which cellular ROS reduce MnO₂ to Mn²⁺, concomitantly shifting fluorescence and electrochemical impedance. The sensor produced consistent signals in chondrocyte senescence models—serial passaging and PPARα siRNA knockdown—and simultaneously exerted ROS-scavenging effects that helped rebalance redox status. In summary, these touch-operable, dual-mode hydrogel sensors discriminate AChE activity/inhibition and ROS-driven cellular senescence while offering adjunctive theranostic benefits via ROS scavenging.

목차 (Table of Contents)

• Overall introduction 1
• Chapter I. Stimuli-Responsive Conductive Hydrogel Touch Sensor for Electrochemical and Fluorescence Monitoring of Acetylcholinesterase Activity and Inhibition 3
• I. Introduction 4
• II. Objective 6
• III. Experimental Section 7
• IV. Results and Discussion 15
• V. Conclusion 36
• VI. Abstract 37
• Chapter II. Touchable Electrochemical Hydrogel Sensor for Detection of Reactive Oxygen Species-induced Cellular Senescence in Articular Chondrocytes 38
• I. Introduction 39
• II. Objective 41
• III. Experimental Section 42
• IV. Results and Discussion 53
• V. Conclusion 93