Rapid determination of immunoglobulin G concentration in cold ethanol precipitation process of raw plasma with near-infrared spectroscopy

Near-infrared spectroscopy (NIRS) is known to be a powerful analytical tool in process monitoring. The feasibility of NIRS was investigated for determination of immunoglobulin G (IgG) in raw plasma cold ethanol precipitation process. Partial least squares (PLS) was used to develop regression model for 63 samples between spectra and reference data measured with a UV spectrophotometer. Three different variable selection methods, including correlation coefficient method, interval partial least squares (iPLS) and successive projection algorithm (SPA), were performed and compared with models based on all the variables. The values of R-c and root mean square error of cross validation (RMSECV) produced by the best model for the calibration set were 0.9599 and 0.6135 g/L, respectively. While for the validation set, the values of R-p and root mean square error of prediction (RMSEP) were 0.9577 and 0.4913 g/L, respectively. The results of this paper demonstrated that NIRS could be a feasible alternative approach for rapid determination of IgG in the cold ethanol precipitation process and can be used as a PAT tool in the future. (C) 2013 Elsevier B.V. All rights reserved.