Microwave Microfluidic Spectroscopy for Biomolecular Measurements in Solution

Communications technology is playing an increasing role in biotechnology and medicine in the form of wearable, implantable, and diagnostic devices. To advance these applications, industry requires quantitative measurements of the electrical properties of biological systems. Here, I will present a range of applications of broadband quantitative electrical measurements in biotechnology, including label-free detection of biomolecules in solution. As an example of this approach, I will present an on-chip, label-free technique to detect conformational changes in a DNA nanomechanical tweezer structure with microwave microfluidics. Through a combination of calibration techniques, we are able to achieve broadband electrical measurements from 40 kHz to 110 GHz, and extract equivalent circuit elements associated with the tweezer opening in solution. Microwave microfluidics is a generalizable, non-destructive technique, making it attractive for high-throughput measurements for medical diagnostics and pharmaceutical development.