Determination of Trace Lead by Near Infrared Spectroscopy with Online Enrichment Technique

Chelating resin D401 enriched trace Pb2+ was directly determined by near infrared reflectance spectroscopy(NIR). The spectra measured were corrected by multiplicative scatter correction (MSC) methods. Partial least squares (PLS) method was used to build model for the MSCcorrected spectra and concentrations of Pb2+. NIR spectra and concentrations of Pb2+ showed a good linear relationship with a maximum correlation coefficient of 0.958 8 when the absorbance in a single wavelength was regressed to the concentration. The PLS model has the minimum root mean square error of prediction (RM-SEP) of 0.869 7 μg/mL and the correlation coefficient of prediction of 0.958 4 when the latent variable number is 2.