Determination of Synthetic and Natural Antioxidants in Cosmetic Preparations by Solid-Phase Extraction and Subsequent Gas and High Performance Liquid Chromatographic Analysis

A gas and a high performance liquid chromatographic method for the simultaneous determination of two additives in o/w cosmetic formulations was developed by using GC and FID, respectively HPLC and UV detection. A solid phase extaraction (SPE) procedure of the sample was required. The separation obtained for the two antioxidants was good under the chromatographic conditions used. Their analysis was carried out in commercial samples, and satisfactory results were obtained for the recovery of these compounds. Cosmetological research has increasingly focused on the processes leading to the formation of the anatomical- functional damage of the skin, identified with ageing. Great interest in this topic has been generated by the study of substances able to prevent cutaneous damage by free radicals: this substances are termed as antioxidants (1). Antioxidant preservatives are able to inhibit reactions promoted by oxygen, thus avoiding the oxidation and rancidity of commonly used fats, oils, waxes, surfactants, perfumes, etc.. In cosmetics they are usually reducing agents and free radical scavangers (2). Cosmetics are commercially available products, that are used to improve the appearance of the skin. The consumer demand for more effective products, that substantively beautify the appearance of the skin, has resulted in increased science research and product development in the cosmetics industry (3). There are considerable data to suggest the benefits of such ingredients in cosmetics (4). In recent years, the cosmetics market has been enriched by numerous skin care products acompanied by advertising claims centred on their antioxidant activity. These products, containing substances with antiradical activity, were created mainly to satisfy expectations of treatment, and prevention of photo-aging (5). Studies in this area, indicate a main association between a potential health hazard and ingestion, and the use of antioxidants in cosmetic products. That is why, it is necessary to establish new efficient analysis methods, for monitoring the use of these controversal antioxidants in an adequate mode, and for the determination, and the admissibility limit control of antioxidants permitted, and used in the cosmetic industry (6).