Electrochemical impedance spectrum frequency optimization of bitter taste cell-based sensors

•EIS frequency optimization of bitter taste cell-based sensors is investigated.•Bitter TRCs, STC-1 and IMITD cells, are used as taste sensing elements.•HEK-293 and dead IMITD cells, without taste receptors, are used as negative control.•EIS data of cell-based sensors under various frequencies is analyzed by SR.•Optimal frequencies of cell-based sensors can be decided.

Electrochemical impedance spectrum frequency optimization to bitter taste receptor cell-based sensors is discussed in this paper. The bitter taste receptor cells (the enteroendocrine STC-1 cells and the ICR mouse isolated taste bud cells) are cultured on carbon screen printed electrodes and used as sensing elements. The HEK-293 cells and dead isolated ICR mouse taste bud cells, without bitter taste receptor expression, are used in negative control experiments. The electrochemical impedance spectrum data is recorded and processed by bistable stochastic resonance for signal-to-noise ratio analysis. The bitter taste receptor cell-based sensor selectively responds to bitter tastants. The tastants species and concentrations can be decided by signal-to-noise ratio parameters. The signal-to-noise ratio eigen peak changes with the shift of electrochemical impedance spectrum frequencies. ICR mouse isolated taste bud cell-based sensor presents bitter tastants perception abilities. 9 kHz is the optimal frequency for STC-1 cell-based sensor measurement. For isolated ICR mouse taste bud cells, 1.2 kHz is the optimal frequency. Negative control experiments results indicate that cells with no taste receptor expression have no discriminating ability for tastant even if they are modulated by different frequencies. The taste cell-based sensor is of great practical value.