Breathable Nanomesh\nHumidity Sensor for Real-Time Skin Humidity Monitoring

Abstract

The importance of monitoring the condition of skin is\nincreasing as its relevance to health is becoming more well understood.\nInappropriate humidity levels can cause atopic dermatitis or hair\nloss. However, conventional film substrates used in electronic skin\nmonitoring devices cause accumulation of sweat or gas between the\ndevice and biological tissue, leading to negative effects in long-term\nhumidity measurements. Thus, real-time measurements of skin humidity\nover long periods are difficult using conventional film devices. Here,\na breathable nanomesh humidity sensor that can monitor skin humidity\nfor a long time is developed by using biocompatible materials such\nas gold, poly­(vinyl alcohol), and Parylene C. The sensor presents\nexcellent gas and sweat permeability and precisely detects the humidity\nlevel of an object for a long time. This study demonstrates the successful\nreal-time detection of the humidity level from human skin and also\ndetects the relative humidity of a plant surface over a prolonged\nperiod. This sensor is expected to have wide applicability for cultivating\ndelicate plants as well as to reveal correlations between skin humidity\nand disease for biomedical applications.