Coplanar stripline microchamber for electrical detection of live and dead biological cells

An improved microchamber for electrical detection of biological cells was designed, fabricated and tested. The microchamber was formed between a gold coplanar stripline fabricated on a sapphire microscope slide and a single microfluidic channel fabricated in a polydimethylsiloxane cover. Compared with the previous design of a coplanar waveguide on a quartz slide with multiple microfluidic channels, the present microchamber was more sensitive, compact, rugged, and transparent. Tests on Jurkat cells in both time and frequency domains demonstrated single-cell sensing potential, as well as discrimination of live vs. dead cells. The test results could be explained by a simple equivalent-circuit model, which efficiently de-embedded the intrinsic cell properties from solution and electrode effects.