Dyes in personal care products. Analysis by miniaturized sample preparation strategies and chromatography coupled to tandem mass spectrometry

Abstract

The main objective of this thesis is to develop analytical methods to determine dyes in cosmetics. This aim involves the development of methodology for oxidative hair dyes, widespread used in hair dyeing products; synthetic dyes in cosmetics and in products intended for children, which are particularly affected by the consumption of dyes; and for the simultaneous analysis of dyes and preservatives, including parabens, in cosmetics. Developed methodologies are based on miniaturized sample preparation techniques and analysis by chromatography coupled to tandem mass spectrometry. Additionally, a first approach to study the photostability of three synthetic dyes in oral care products is performed. These results constitute a precedent in the photodegradation of synthetic dyes in cosmetics.