Highly Biocompatible Antibacterial Hydrogel for Wearable Sensing of Macro and Microscale Human Body Motions

• Published in: Small (Weinheim an der Bergstrasse, Germany) Vol. 20; no. 37; pp. e2401201 - n/a
• Main Authors: Cheng, Hsin, Keerthika Devi, Ramadhass, Huang, Kuan‐Yeh, Ganesan, Muthusankar, Ravi, Sai Kishore, Lin, Chun Che
• Format: Journal Article
• Language: English
• Published: Germany Wiley Subscription Services, Inc 01-09-2024
• Subjects: Anti-Bacterial Agents - chemistry; Anti-Bacterial Agents - pharmacology; antibacterial activity; Antiinfectives and antibacterials; Biocompatibility; Biocompatible Materials - chemistry; Biocompatible Materials - pharmacology; Borates; Borax; Cell Survival - drug effects; E coli; Effectiveness; Electrical resistivity; electronic skin; Electronics; Escherichia coli - drug effects; Flexible components; Humans; Hydrogels; Hydrogels - chemistry; Interfacial properties; konjac glucomannan; Light irradiation; Mannans - chemistry; Mannans - pharmacology; Metal Nanoparticles - chemistry; Microorganisms; Nanoparticles; Polyvinyl alcohol; Polyvinyl Alcohol - chemistry; self‐healing; Sensors; Silver; Silver - chemistry; Silver - pharmacology; Staphylococcus aureus - drug effects; strain sensor; Tensile strength; Wearable Electronic Devices; Wearable technology; antibacterial activity; electronic skin; konjac glucomannan; polyvinyl alcohol; strain sensor; self‐healing
• ISSN: 1613-6810; 1613-6829; 1613-6829
• DOI: 10.1002/smll.202401201

Flexible electronics, like electronic skin (e‐skin), rely on stretchable conductive materials that integrate diverse components to enhance mechanical, electrical, and interfacial properties. However, poor biocompatibility, bacterial infections, and limited compatibility of functional additives within polymer matrices hinder healthcare sensors' performance. This study addresses these challenges by developing an antibacterial hydrogel using polyvinyl alcohol (PVA), konjac glucomannan (KGM), borax (B), and flower‐shaped silver nanoparticles (F‐AgNPs), referred as PKB/F‐AgNPs hydrogel. The developed hydrogel forms a hierarchical network structure, with a tensile strength of 96 kPa, 83% self‐healing efficiency within 60 minutes, and 128% cell viability in Cell Counting Kit‐8 (CCK‐8) assays, indicating excellent biocompatibility. It also shows strong antibacterial efficacy against Gram‐negative Escherichia coli (E. coli) and Gram‐positive Staphylococcus aureus (S. aureus). Blue light irradiation enhances its antibacterial activity by 1.3‐fold for E. coli and 2.2‐fold for S. aureus. The hydrogel's antibacterial effectiveness is assessed by monitoring changes in electrical conductivity, providing a cost‐effective alternative to traditional microbial culture assays. The PKB/F‐AgNPs hydrogel's flexibility and electrical conductivity enable it to function as strain sensors for detecting body movements and facial expressions. This antibacterial hydrogel underscores its potential for future human‐machine interfaces and wearable electronics.
In this study, a versatile hydrogel for electronic skin (e‐skin) is synthesized by combining polyvinyl alcohol, konjac glucomannan, borax, and flower‐shaped silver nanoparticles. The resulting hydrogel exhibits exceptional mechanical strength (96 kPa) and remarkable elongation capacity (1041%), alongside high biocompatibility (cell viability: 128%) and impressive self‐healing properties, essential for e‐skin functionality.