Capacitive Biosensing of Skin Irritants Using a Lanolin-Based Artificial Stratum Corneum Model

Skin irritation testing is transitioning toward non-animal alternatives that can replicate the functional properties of the human stratum corneum (SC). To address this need, we report a capacitive biosensing platform that integrates a lanolin-based artificial SC (aSC) for rapid, indicator-free detection of chemical irritants. The approach leverages a membrane-bound lipid matrix to detect changes in interfacial capacitance caused by chemical exposure. Among candidate materials, lanolin emerged as the most effective SC mimic, showing reproducible baseline stability and responsive dielectric shifts. The system quantifies barrier integrity through the capacitance change rate (ΔC/Δt), which serves as a real-time indicator of irritation potential. By positioning the biosensor as an analog of the SC and monitoring the dielectric environment during short exposures (7.5 min), we shift the paradigm from endpoint-based biochemical assays to rapid, physicochemical screening. This concept supports the advancement of ethical, scalable testing platforms that reduce reliance on animal or cellular models while maintaining sensitivity to barrier-compromising agents.