A system and method for analysis of fluids, particularly bodily fluids such as saliva, uses an active, electrically-driven substrate for supporting an amalgamate of fluid and nanoparticles selected to adhere to one or more proteins. The nanoparticles affect light that is directed on or through the amalgamate. Different light directions, light polarization planes, and light wavelengths are used to obtain optical properties of the amalgamate. Once obtained, these values are compared to earlier or baseline values to determine a property of the amalgamate. Values or ranges are compared to earlier values, suitably with empirical association with maladies or conditions, to facilitate detection or diagnosis.
