Multivariate Determination of Human Serum Albumin and γ-Globulin in a Phosphate Buffer Solution by near Infrared Spectroscopy

Abstract

Near infrared (NIR) spectra in the 1300–1850 nm region were measured for phosphate buffer solutions containing both human serum albumin and γ-globulin with various concentrations. The concentrations of albumin and γ-globulin were determined by partial least squares (PLS) regression analysis. The calibration for albumin in the concentration ranges of 0.100–8.000 g dL−1 yielded the correlation coefficient ( R) of 0.998, the standard error of calibration ( SEC) of 0.124 g dL−1, and the standard error of prediction ( SEP) of 0.152 g dL−1, respectively. Those for γ-globulin in the concentration ranges of 0.100–6.000 g dL−1 yielded were 0.998, 0.110 g dL−1 and 0.118 g dL−1, respectively. The regression coefficients ( RCs) of PLS factors for albumin were compared with those for γ-globulin. The differences were discussed for each RC between albumin and γ-globulin. The coefficient of variation ( CV) was calculated to be 0.0388 and 0.0374 for albumin and γ-globulin, respectively. The ratio of standard derivation of reference data in prediction set to SEP ( RPD) are 13.4 and 16.4 for them. These values obtained in the present study satisfy the demands of clinical analysis of blood. The present results demonstrate that it is possible to determine the concentrations of the two kinds of proteins in the solution simultaneously by use of NIR and PLS regression.