Can chiroptical spectroscopy be used for the analysis of blood plasma?

As an improvement on currently used methods of molecular spectroscopy, we used chiroptical techniques (electronic circular dichroism, fluorescence detected circular dichroism, and Raman optical activity [ROA]) to investigate the human blood plasma. To avoid the degradation of plasma samples, we measured them directly without any further preparation. We also tested cutoff weight filters (Amicon Ultra 100, 30, 10, and 3 kDa by Merck Millipore) to reduce undesirable fluorescence in the ROA and Raman spectra and also to remove the most abundant protein in the plasma-human serum albumin. The obtained spectra show that the ultrafiltration has a positive effect on undesirable fluorescence in ROA and Raman and also could reduce the amount of albumin in the plasma. Our results suggest that blood plasma can be successfully measured by the aforementioned methods. Therefore, these methods can potentially be useful for following research in the development of new, noninvasive, and reliable screening methods of clinical diagnostics.