Abstract
<jats:p>Optical and wearable biomedical technologies show systematic bias, performing less accurately on darker skin due to melanin-driven absorption and scattering of light. This leads to problems for patients, including delayed detection of clinical symptoms, reduced trust in wearable health systems, and a higher risk of misdiagnosis or inappropriate treatment recommendations. In this study, we introduce a flexible epidermal model that reproduces the key optical and thermal characteristics of the human epidermis. The model consists of a polydimethylsiloxane matrix with tunable concentrations of polydopamine nanoparticles, which mimic the broadband absorption of melanin in the skin. The resulting thin and flexible membranes exhibit six controlled pigments, realistic reflectance (4-7%), and transmittance (85-90%), as well as absorption (0.2–5 mm⁻¹) and scattering (0.8–2.5 mm⁻¹) coefficients that match in-vivo data. Thermal analysis confirms pigmentation-dependent photothermal conversion and thermal conductivities within the physiological range.</jats:p>