Differentiation of lipsticks using the shifted excitation Raman difference spectroscopy supported by chemometric methods

Abstract

The objective of this paper was to evaluates the shifted excitation Raman difference spectroscopy at 784 nm and 785 nm excitation wavelength for the non-destructive identification of 70 lipsticks of different brands and Product line, overcoming the lipstick fluorescence problem reported by previous works using Raman techniques. Full Raman spectra were analyzed from the different samples, any sample was selected to test homogeneity of lipstick samples. The results of this paper demonstrate that the shifted excitation Raman difference spectroscopy can effectively suppress the interference of fluorescence compared to the general Raman spectra,in combination with multivariate methods,a new method for the identification of lipstick was established. The visual classification delivered a high value of discriminating power i.e. 100%. Cluster analysis provided 99.88% discriminating power combined with Principal component analysis. The results of this study demonstrated that the shifted excitation Raman difference spectroscopy supported by chemometric methods was a new method for the identification of lipstick samples.