A biosensor is proposed for insertion into the subcutaneous tissue of a user wherein the biosensor includes at least one flexible substrate (2) and at least one electrode (5) on at least one surface (9) of the substrate and at least one contacting element (3). The contacting element is connected to the electrode. The substrate has at least one kink (4), at which the substrate is at least partly kinked such that the surface is subdivided into at least two interconnected outer surfaces (9a, 9b, 9c).