Functional microneedles for wearable electronics

Abstract

With an ideal comfort level, sensitivity, reliability, and user‐friendliness, wearable sensors are making great contributions to daily health care, nursing care, early disease discovery, and body monitoring. Some wearable sensors are imparted with hierarchical and uneven microstructures, such as microneedle structures, which not only facilitate the access to multiple bio‐analysts in the human body but also improve the abilities to detect feeble body signals. In this paper, we present the promising applications and latest progress of functional microneedles in wearable sensors. We begin by discussing the roles of microneedles as sensing units, including how the signals are captured, converted, and transmitted. We also introduce the microneedle‐like structures as power units, which depend on triboelectric or piezoelectric effects, etc. Finally, we summarize the cutting‐edge applications of microneedle‐based wearable sensors in biophysical signal monitoring and biochemical analyte detection, and provide critical thinking on their future perspectives.

Bioinspired Adaptable Indwelling Microneedles for Treatment of Diabetic Ulcers

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Mechanically Robust Dissolving Microneedles Made of Supramolecular Photosensitizers for Effective Photodynamic Bacterial Biofilm Elimination

“…Mechanically robust dissolving microneedle (DMN) patch can penetrate the compact EPS barrier of biofilms to deliver antibacterial agents effectively, thus showing great promise for eliminating biofilms. − Herein, for the first time, we developed a DMN patch composed of a supramolecular photosensitizer (SP) for enhanced penetration and photodynamic elimination of bacterial biofilms (Scheme ). Tetra­(4-pyridyl)-porphine (TPyP), a commonly used porphyrin derivative, was successfully included into sulfobutylether-β-cyclodextrin (SCD) through supramolecular interactions.…”

A mussel-inspired semi-interpenetrating structure hydrogel with superior stretchability, self-adhesive properties, and pH sensitivity for smart wearable electronics

“…As the demand for health detection steadily increased, the potential of wearable flexible sensors has received attention from various researchers and commercial markets due to their advantages of small size, flexibility, and stability. 1–3 Owing to their unique combination of hydrogel and conductive substances, conductive hydrogels are viewed as a perfect material for flexible sensors, holding substantial application prospects in detecting biophysical signals such as motion, heart rate, blood pressure, respiratory rate, etc. 4–7…”