Radio frequency detection and analysis of synthetic particles

Radio-frequency (RF) measurements provide a potentially label-free approach for quantitative analysis of cells and particles in microfluidic channels. We demonstrate an interference based RF sensor which operates from 5 MHz to 2 GHz at high sensitivity. Millimeter-sized gold and amazonite particles show particle position, size, and material strongly affect quantitative RF measurements. Lossy materials do not significantly reduce the effective quality factor, which is as high as 30,000 at 1.2 GHz, of the sensor. Thus, the sensor is particularly suitable for biomedical applications such as skin cancer detection and the development of novel label-free and all electronic rheological instrumentation.