EIT-Inspired Microfluidic Cytometer for Single-Cell Dielectric Spectroscopy

A new microfluidic cytometer for single-cell dielectric spectroscopy is proposed in this paper and analyzed in silico by means of a finite-element model. The device, inspired by electrical impedance tomography, includes two circumferential arrays of electrodes instead of just two pairs of coplanar or parallel-facing electrodes, thus allowing a great versatility in stimulation and measurement patterns. In particular, using stimulation patterns with different spatial orientation provides information on cell morphology, besides quantitative cell-volume estimation. Moreover, the performance limitation at low frequency due to electrode polarization is overcome, owing to a peculiar recording scheme: Current is injected between an electrode pair, and the resulting voltages are measured at remaining electrodes using high-input impedance differential amplifiers. These features significantly enhance the cytometer discrimination capabilities.