The invention relates to a sensor (2) including: a microelectrode assembly (21) and β-pancreatic cells (23) or islets (230) of Langerhans in culture on the microelectrode assembly (21) characterized in that the microelectrode assembly (21) is designed to measure dynamically, continuously and in real time, electrical signals (V) produced by the β-pancreatic cells (23) or the islets of Langerhans (230) upon physiological activation. The invention also relates to the field of devices that can be implantable in in the body of a patient, and including an insulin dispenser for dispensing an amount of insulin. The invention also relates to a method for manufacturing such a sensor and to such a device and a use of such a sensor.