Visible light-responsive mechanically and electronically controllable conductive carbon dot-hydrogel-based pressure-strain sensor for wireless monitoring of antifouling performance

This work describes the visible-light-induced wireless pressure and strain sensor based on carbon dot (CD) loaded conductive hydrogel for the mechanical force-regulated antifouling behavior. The conductivity, as well as pressure and strain sensitivities of the hydrogel, were modulated by modifying the hydrophobic–hydrophilic transformation of the CD components that controlled the antifouling effect through mild mechanical forces, allowing the cells to be squeezed out from the hydrogel. The photocatalytic activity of the CD containing carbonized polydopamine (cPDA) releases the cPDA which enhances the network formation, resulting in a four-fold higher conductivity, 158% enhanced mechanical strength, and 231% improved stretchability, which enhances the pressure and strain sensing response. Furthermore, antifouling phenomenon involved in the physical deformation associated with the changes in the electrochemical behavior of the hydrogel, which was monitored by wireless sensing, demonstrated the effect of mechanical force on the antifouling behavior for the successful removal of cells from the hydrogel. Additionally, the efficacy of the antifouling effect depending on pressure or strain was evaluated by real-time monitoring of the wireless response. This antifouling property of the hydrogel together with visible-light-controlled hydrophobic–hydrophilic transformation can allow the development of hydrogel-based electronics for electronic skin sensors, prosthetics, and biosensing applications. [Display omitted] •Conductive carbon dot-hydrogel applied for visible-light tunable pressure-strain sensor.•Increased hydrophilicity accelerates the mechanical strength and stretchability.•Reversible sensor increasing the stability from 2240 to over 3000 strain cycles.•Twisting force achieved 100% antifouling, only 42% observed for motion free treatment.•Mechanical force regulated antifouling monitored using wireless communication.