Analysis of Glucocorticoids as Potential Adulterants in Cosmetic Products: A Dual Approach for Qualitative and Quantitative Evaluation Based on ELISA and HPLC-MS Methods

The analysis of cosmetic products represents an important field of analytical chemistry, since the demand for new formulations is continuously increasing. Regulations about prohibited/regulated compounds are applied in each country. Among the substances that are banned in cosmetics, corticosteroids represent a potential harm for consumers since the prolonged exposure to these compounds can affect health status. However, corticosteroids can be found in cosmetics as an illegal addition since they are able to alleviate the symptoms of inflammatory skin problems. In this work, two different approaches for detecting corticosteroids as potential adulterants in cosmetic products were compared. First, a reversed-phase HPLC-MS method was optimized and fully validated in order to identify and quantify eight corticosteroids (methylprednisolone, beclomethasone, flunisolide, budesonide, betamethasone 17-valerate, beclomethasone dipropionate, flumethasone, and dexamethasone). This reference method was then compared with an enzyme-linked immunosorbent assay (ELISA). Indeed, immunological techniques allow for rapid, low-cost, and sensitive detection of target analytes even in complex matrices, and they can be performed with simple instrumentation and by non-skilled personnel. The application of these methods on spiked cosmetic products was compared in terms of performance and advantages in order to evaluate the possibility of exploiting a complementary approach for optimizing the time for and costs of the analysis.