A method for detecting in vivo characteristics of a biosensor (110) is disclosed. Here, the biosensor (110) is configured to electrochemically determine at least one value of the analyte (136) in the sample of body fluid (140) in interaction with the electronic unit (202). , The biosensor (110) comprises at least one working electrode (120), the working electrode (120) is covered by a membrane (132) and contains an enzyme (134) for causing a reaction with the analyte (136). Including, the membrane (132) has an electrical resistance and the working electrode (120) has an electrical capacity. In addition, the electronic unit (202) is configured to measure the current response and raw current, which indicates the admittance of the biosensor (110). Here, the method includes a) a step of providing a sensitivity vs. admittance relationship of the biosensor (110), b) a step of measuring the raw current in the biosensor (110), and c) a biosensor (110). ), The step of measuring the in vivo current response indicating the in vivo admittance, wherein the in vivo current response is at at least one first operating point (156) and at least one second operating point (158). Measured at, the first operating point (156) was selected to provide a first characteristic value related to the electrical resistance of the membrane (132), and the second operating point (158) was the working electrode (120). The steps selected to provide a second characteristic value related to the electrical capacity of the d) using raw current and using the first characteristic value to determine the actual value of sensitivity. To determine the value of the admittance (136) in the sample of body fluid (140) by compensating for the in vivo sensitivity drift in the biosensor (110) by correcting the measured value for the raw current. Thus, the biosensor is based on the step a) considering the sensitivity vs. admittance relationship as provided during step a) and e) the first characteristic value and / or t
