A system for the estimation of at least one physical parameter of a region of a biological and/or physiological medium comprising at least one electrolyte, said system comprising: - at least two electrodes, of which at least one working electrode and at least one counter electrode, configured to come into contact with the region of the medium; - a current generator configured to deliver to the electrodes a train of electric pulses of current, each electric pulse having a pulse duration; - a computer-readable memory comprising at least one predefined analytic model (M(t)) of an electric potential, between the working electrode and the counter electrode, as a function of time, receiving as inputs at least the current and the pulse duration and comprising at least one physical parameter of the medium to be estimated; - an acquisition unit comprising a signal amplifier configured to acquire and amplify an electric potential recorded by the electrodes; and - a processor comprising: • a stimulation module configured to control the current generator so as to deliver a biphasic charge-balanced current, comprising electric pulses, during a stimulation duration (Ts); • an acquisition module configured to trigger an acquisition of an electric potential variation as a function of time (ΔV(t)) during a time window (Tm) comprised in the stimulation duration (Ts); and • a calculation module configured to receive the acquired electric potential variation of the region of the medium between the working electrode and the counter electrode as a function of time (ΔV(t)), fit the acquired electric potential variation as a function of time (ΔV(t)) using the predefined analytic model (M(t)) retrieved from the computer-readable memory, and output a value of the physical parameter obtained from the fitting of the predefined analytic model (M(t)); said system characterized in that the predefined analytic model (M(t)) is obtained from the coupling of an analytical model of the electric field generated by the electrodes with a double layer model generated at the electrode-medium interface, said coupling accounting for contributions from the electrode-electrolyte interface. - at least two electrodes, of which at least one working electrode and at least one counter electrode, configured to come into contact with the region of the medium; - a current generator configured to deliver to the electrodes a train of electric pulses of current, each electric pulse having a pulse duration; - a computer-readable memory comprising at least one predefined analytic model (M(t)) of an electric potential, between the working electrode and the counter electrode, as a function of time, receiving as inputs at least the current and the pulse duration and comprising at least one physical parameter of the medium to be estimated; - an acquisition unit comprising a signal amplifier configured to acquire and amplify an electric potential recorded by the electrodes; and - a processor comprising: • a stimulation module configured to control the current generator so as to deliver a biphasic charge-balanced current, comprising electric pulses, during a stimulation duration (Ts); • an acquisition module configured to trigger an acquisition of an electric potential variation as a function of time (ΔV(t)) during a time window (Tm) comprised in the stimulation duration (Ts); and • a calculation module configured to receive the acquired electric potential variation of the region of the medium between the working electrode and the counter electrode as a function of time (ΔV(t)), fit the acquired electric potential variation as a function of time (ΔV(t)) using the predefined analytic model (M(t)) retrieved from the computer-readable memory, and output a value of the physical parameter obtained from the fitting of the predefined analytic model (M(t)); • a stimulation module configured to control the current generator so as to deliver a biphasic charge-balanced current, comprising electric pulses, during a stimulation duration (Ts); • an acquisition module configured to trigger an acquisition of an electric potential variation as a function of time (ΔV(t)) during a time window (Tm) comprised in the stimulation duration (Ts); and • a calculation module configured to receive the acquired electric potential variation of the region of the medium between the working electrode and the counter electrode as a function of time (ΔV(t)), fit the acquired electric potential variation as a function of time (ΔV(t)) using the predefined analytic model (M(t)) retrieved from the computer-readable memory, and output a value of the physical parameter obtained from the fitting of the predefined analytic model (M(t)); said system characterized in that the predefined analytic model (M(t)) is obtained from the coupling of an analytical model of the electric field generated by the electrodes with a double layer model generated at the electrode-medium interface, said coupling accounting for contributions from the electrode-electrolyte interface.