Electromagnetic techniques can provide a means for rapidly analyzing or processing biochemical samples in a manner that can be readily scaled up to handle large numbers of samples in massively parallel, low-cost analysis systems that do not rely on optical or aptamer-based labels. Before such systems can be realized, the electromagnetic response of biochemical samples must be understood in detail, in order to determine relevant biochemical properties that can be detected or influenced by electromagnetic signals. Detailed investigations of the electromagnetic response of chemical reagents and biomolecules have been hampered by a lack of robust and quantitative measurement techniques, particularly when available fluid volumes are limited.

To address these issues, we have developed accurate measurements of the electromagnetic response of nanoliter fluid volumes over the broad frequency range 100 Hz to 110 GHz by integrating microfluidic channels with microelectronic circuit elements and advanced on-wafer microwave measurement techniques. Such an experimental platform allows us to determine quantitatively the broadband frequency-dependent permittivity and/or permeability functions of small volumes of liquid samples as a function of temperature, composition, and concentration. These measurements can yield information on the polarization dynamics of different conformations in DNA nanomachines and protein suspensions. Understanding the polarization dynamics of relevant molecules and solutions can lead to new electromagnetic detection and processing approaches for fundamental chemical, biological, and biophysical investigations.