LBL Noninvasively Peelable Biointerfacial Adhesives for Cutaneo‐Inspired pH/Tactility Artificial Receptors

Abstract Besides barrier functions, skin possesses multiple sentiences to external stimuli (e.g., temperature, force, and humidity) for human‐outside interaction. Thus, skincare should be taken very seriously, especially by patients with sensory disorders. However, currently available skin‐mimicking devices are always limited by so much insufficient response functions and nontunable interface behaviors so as not to realize precise health monitoring and self‐defense against injury. Herein, a bioinspired cutaneous receptor‐perceptual system (CRPS) patch is presented, integrating hybrid pH indicators and triboelectric nanogenerators into biointerface film‐adhesives that are fabricated through facile layer‐by‐layer (LBL) self‐assembly of amide and Schiff‐base linkages between alginate grafted with N‐hydroxysuccinimide ester (AN), tannic acid (TA), and polyethylenimine (PEI). This CRPS patch is adhered robustly to the soft‐curved skin surface without failure via “molecular suturing,” and amino acid enables its benign peel‐on‐demand from tissue interfaces. Postdamage self‐healing brings it without surgical reoperation, avoiding extra cost, pain, as well as infection risks. Significantly, CRPS patches as artificial chemo/mechanoreceptors can remotely visualize skin physiological status by pH‐induced chromism using smartphones and prevent skin contact injury by tactility‐driven self‐powered electrical signals. Overall, the LBL‐based strategy to create controllably biointerface‐adhesive CRPS patches will usher in a new era of the mobihealth care platform supporting smart diagnosis and self‐protection.