APPLICATION OF MOLECULAR-SPECTROSCOPY IN THE MIDINFRARED REGION TO THE DETERMINATION OF GLUCOSE AND CHOLESTEROL IN WHOLE-BLOOD AND IN BLOOD-SERUM

The feasibility of applying molecular spectroscopy in the mid-infrared region to the quantitation of glucose and cholesterol in whole blood and in blood serum was examined by measuring the samples in the dry st ate on a polyethylene carrier, The partial least-squares (PLS) algorit hm was employed to set up the calibration models. Analysis was perform ed by normalizing the spectra to a standard area, Evidence that this a pproach is warranted was obtained through experiments where potassium thiocyanate served as the internal standard. The following average PRE SS1/2 values (PRESS stands for prediction residual error sum of square s) emerged from the calibration: glucose, 22.3 mg/dL; cholesterol, 31. 3 mg/dL. Such errors are comparable with those achieved in attenuated total reflectance (ATR) measurements, The calibration models set up fa r blood serum samples fit better than those for whole blood samples. I f the procedure of sample application onto the carrier is improved, th e method may work well for the determination of glucose and cholestero l in whole blood and in blood serum.