Quantitative analysis of hormones in cosmetics by LC-MS/MS combined with an advanced calibration model
Abstract
In this contribution, tandem mass spectrometry coupled with liquid chromatography (LC-MS/MS) was combined with the multiplicative effects model for mass spectroscopy (MEMMS) to quantitatively determine three hormones (i.e. estrone, hydrocortisone and progesterone) in cosmetics (toner and essence emulsion). The adoption of the MEMMS model in the analysis of LC-MS/MS data was to address the problem of sensitivity and signal instability of LC-MS/MS over time caused by the gradual fouling of the ion source, vacuum instability, drifting of baseline, ion suppression, etc. Experimental results showed that the MEMMS model could effectively mitigate the detrimental effects of the signal instability of LC-MS/MS over time, and achieve quite accurate quantitative results for estrone, hydrocortisone, and progesterone in both toner and essence emulsion samples with average relative prediction error values no larger than 10.0%, which were far lower than the corresponding values (11.5–67.4%) of the conventional univariate internal standard calibration method based on peak height ratios between the peak of the target analytes and that of the internal standard.