Firstly, this work demonstrates that contactless dielectrophoresis (cDEP) was useful to detect a reversal in the electrical phenotype of late-stage ovarian cancer cells to a profile similar to that of slow-growing early-stage ovarian epithelial cells after treatment with a non-toxic bioactive metabolite, sphingosine. Current chemotherapeutics are highly toxic to patients and can cause severe adverse side effects, so non-toxic treatments that could slow or reverse cancer growth would be advantageous. This is the first instance of cDEP for detecting induced changes in cell structure, showing its potential as a rapid, non-biomarker-based drug screening platform.

Specifically, low frequency contactless dielectrophoresis devices previously designed by Sano et al were used to extract the crossover frequency and specific membrane capacitance of early and late stage mouse ovarian surface epithelial (MOSE-E and MOSE-L) cells when untreated, treated with the anti-cancer sphingosine (So) metabolite and with a generally cancer-supporting sphingosine-1-phosphate (S1P) metabolite. The specific membrane capacitance of MOSE-L cells treated with So decreased and the normalized crossover frequency increased to levels matching MOSE-E cells.

Secondly, a new multilayer cDEP device featuring curved interdigitated electrode channels overlaying a straight sample channel for the purpose of cell sorting was designed, computationally modeled, fabricated, and tested. The goal of this design was to achieve continuous multi-stream sorting of cells, and preliminary testing demonstrated that prostate cancer PC3 cells were continuously deflected toward the top of the channel under an electric field, as predicted by the numerical model.