This paper presents a flexible and disposable humidity sensor based on Poly (3,4ethylenedioxythiophene):polystyrene sulfonate (PEDOT:PSS). The sensing layer is developed by drop casting PEDOT:PSS on screen printed graphene-carbon (G-C) ink based interdigitated electrodes (IDEs) on paper substrate. The humidity sensing properties are investigated in a wide humidity range (25 %RH -90 %RH) at room temperature (RT; 27 ºC ± 2 ºC). The sensor exhibits substantial % response (118.5 % at 90 %RH) in the considered range with response/recovery time as 70/30 seconds (sec). The applicability of the sensor has been demonstrated for skin moisture/humidity monitoring under normal and moist conditions. A read-out circuit is designed for demonstrating the real-time monitoring of skin moisture level. The obtained results indicate the suitability of the developed sensor for applications such as skin moisture monitoring, environmental humidity monitoring, non-contact switching, agriculture, and healthcare industries.

Highly sensitive pressure sensors with features such as biocompatibility, biodegradability, and flexibility are needed in applications such as robotics, prosthesis, medical implants, and wearable electronics. However, due to material limitations or technological bottlenecks it is often challenging to fabricate pressure sensors with these attributes at the same time. Herein, we present biodegradable silk/PEO/yeast nanofibers based soft capacitive pressure sensor array (2 × 2). The electrospun nanofibers used here have about 150% enhanced crystallinity, as confirmed by X-ray diffraction (XRD) and Fourier Transform-Infrared spectroscopy (FT-IR). The performance metrics of the sensor array, such as sensitivity (~0.18 kPa -1 ), hysteresis (<16%), minimum response (~0.8 s), and recovery time (~1 sec) show its suitability for application such as smart plasters used for accelerated wound healing. Further, the degradability studies confirm the quick degradation of sensors, which can also be potentially controlled with suitable packaging.