A sensing device is provided. The sensing device includes a transistor, a disposable electrode, and a remote electrode. The transistor includes an extended gate, source and drain. The remote electrode is configured to receive a reference voltage. The disposable electrode is coupled between the transistor and the remote electrode. The disposable electrode includes a proximal end and a distal end. The proximal end of the disposable electrode is coupled to the extended gate of the transistor. The distal end of the disposable electrode is coupled to the remote electrode. The disposable electrode is adapted to load a cell and receive a membrane potential of the cell. The disposable electrode provides a gate voltage to the extended gate based on the change of the membrane potential and the reference voltage. The transistor provides different transistor currents at the drain based on the change of the gate voltage. |