Scalable Wearable and Biocompatible Temperature Sensor: Integrating Laser-Reduced Graphene Oxide on Chitosan-PEG Membranes Badillo-Hernández, Jorge Ángel Mebarek, Siham Hernández, Lidia Lizbeth Rivadeneyra, Almudena Reyes-Valderrama, María Isabel Olguín-Iglesias, Alejandro Rodriguez, Noel Vazquez-García, Rosa Angeles Rodríguez-Lugo, Ventura Bramini, Mattia Moraila-Martinez, Carmen Lucía Alemán-Ayala, Karina 3D charge transport | biocompatibility | chitosan | electrical properties | LrGO (laser-reduced graphene oxide) | mechanical flexibility | mott variable range hopping | PEG | thermal sensitivity Flexible, cytocompatible, scalable temperature sensors are essential for bioelectronic devices. Here, a flexible sensor is fabricated using a chitosan–poly(ethylene glycol) (CS–PEG) matrix embedded with laser-reduced graphene oxide (LrGO). Laser-assisted reduction enhances conductivity and generates a stratified, porous microstructure that supports efficient percolation while maintaining flexibility. The sensor shows a stable, highly sensitive thermal response, with a temperature coefficient of resistance (TCR) of − 1 . 174 %◦C − 1 and a sensitivity of − 1457 . 02 Ω◦C − 1 across 30◦C to 90◦C . Impedance spectroscopy shows that the resistive configuration at 500Hz yields an almost linear response (R2 = 0.996), while capacitive behavior and humidity variations ( 30 %to 90 % RH) induce minor impedance changes ( < 15%). Under a 30◦C - 60◦C - 30◦C step, the device shows reversible electrical changes, with a response time of 43 s , recovery of 355 s , minimal hysteresis ( < 1 . 1 % ), and stable performance over 48 h . Bending tests up to 100 % strain for 200 cycles produce moderate resistance variation (R/R0 ≤ 1.88), confirming mechanical robustness. On-skin measurements from 22◦C to 35 . 3◦C show a ≈22 % resistance decrease. Charge-transport analysis agrees with Mott’s hopping model. Cell-culture assays confirm high viability ( > 90 % ). The scalable, solvent-free, metal-free fabrication highlights the CS–PEG–LrGO sensor as a promising platform for wearable biosensing. 2026-02-13T08:50:23Z 2026-02-13T08:50:23Z 2025-12-29 journal article Scalable Wearable and Biocompatible Temperature Sensor: Integrating Laser‐Reduced Graphene Oxide on Chitosan‐PEG Membranes. Jorge Ángel Badillo‐Hernández, Siham Mebarek, Lidia Lizbeth Hernández, Almudena Rivadeneyra, María Isabel Reyes‐Valderrama, Alejandro Olguín‐Iglesias, Noel Rodriguez, Rosa Angeles Vazquez‐García, Ventura Rodríguez‐Lugo, Mattia Bramini, Carmen Lucía Moraila‐Martinez, Karina Alemán‐Ayala. 2025, Advanced Materials Technologies, e01249 https://hdl.handle.net/10481/110950 10.1002/admt.202501249 eng ;e01249 http://creativecommons.org/licenses/by-nc-nd/4.0/ embargoed access Attribution-NonCommercial-NoDerivatives 4.0 Internacional Wiley-VCH GmbH