This paper reports on the application of dielectrophoresis techniques in the radiofrequency range, in order to probe inner dielectric specificities and therefore characterize individual biological cells. The novelty of this work consists in exploring the capability of UHF signals to generate DEP-driven motion effects on flowing biological cells in a microfluidic micro-device. Additionally, with applied signals above 50MHz, distinct cross-over frequencies can be identified as function of both the cell type and the difference in the intracellular dielectric features, and between in-tracellular and extracellular media. Several experimental campaigns were led on three distinct cell lines by thoroughly scanning the UHF spectrum and specifically measuring the resulting second cross-over frequency for each cell type. The experimental results suggest that significant cross-over frequency differences can be observed from one cell line to the other and confirm that their high frequency DEP characteristics can be a relevant cell signature for discriminating them. This work is a first step towards the development of a UHF-DEP cytometer.