CMOS Biosensor IC with 360-Sensing Elements Using 63-GHz LC-Oscillator and DEP for Label-Free Single-Cell Detection

For label-free single-cell detection, a CMOS biosensor integrated circuit (IC) with 360-sensing elements using 63-GHz LC-oscillator and single-cell trapping electrode is proposed. To realize a label-free biosensor, we have focused on frequencies around 60 GHz where changes in the dielectric constant of water become prominent as many a water molecule is bound to biomolecules, we reported an LC-oscillator based sensor previously. LC-oscillator based sensor has the highest sensitivity at the center of differential terminals of inductor. To attract single cells onto the sensing position using dielectrophoresis (DEP), cell-sized electrode is placed at the center of the differential electrodes. The measurement results of trapped cells vary widely suggesting the variation of cell volume and cell activity.