Determination of Na in milk samples by laser induced breakdown spectroscopy

Laser-induced breakdown spectroscopy (LIBS) technique has a powerful application in elements detection, so it has become a popular object for scholars. In this article, the Na content of milk samples is detected using LIBS. A total of 15 milk samples are analyzed, of which 9 known samples are used as the calibration samples, and a regression model for quantitative analysis of Na is established by using the method of partial least squares (PLS); other 6 samples are used as the test samples to verify the results of quantitative analysis by the model. The LIBS is used to detect the Na content in 6 test samples, and the linear correlation coefficient between reference content and predicted content is 0.993 8 with the relative error less than 15%. LIBS technology can rapidly and accurately measure the Na content in the milk, which indicates a great application potential.