Many diseases manifest themselves through physiological changes in the skin. The monitoring of disease-associated metabolites in the skin using biosensors is a rapidly growing technology that allows the control and diagnosis of diseases almost in real time and with great comfort for the users. There are currently two major technological trends. Biosensors integrated (tattoo sensors) in the dermis and biosensors attached to the epidermis (wearable sensors). The contact surface between the biosensors and these skin tissues and fluids is critical to ensure biocompatibility, sensitivity to the target metabolite, comfort for the user, security and several other features. In general, the surfaces of the biosensors are made of functional biopolymers. This article summarizes the characteristics of the biopolymers currently used in the construction of skin biosensors intended for glucose monitoring in sweat.