Special considerations in eye cosmetics

Abstract

An innovative and simple single drop ionic liquid based non-dispersive microextraction (SDILNDµE) method has been proposed for enrichment of arsenic (As), cadmium (Cd), nickel (Ni) and lead (Pb) in eye makeup products prior to analysis with electrothermal atomic absorption spectrometry (ETAAS). A narrow glass column was used to provide more contact area by enhancing the phase transfer ratio between two media (extractive and aqueous). Improved recoveries of the hydrophobic complexes of metals and metalloid with ammonium pyrrolidinedithiocarbamate (APDC) extracted into the 1-butyl-3-methylimidazolium hexafluorophosphate [C4mim] [PF6] were achieved. Several parameters were systematically optimized. At optimum conditions, limit of detection (LOD) for Cd, As, Pb and Ni was attained as 0.086, 0.049, 0.126 and 0.262 μgL−1, correspondingly with relative standard deviation < 5%. Spike recovery study was carried out in the real samples to check the precision of proposed methodology. The proposed method was productively practiced on the real sample for simultaneous enrichment of toxic elements (As, Ni, Pb and Cd) in eye makeup products. Principal component analysis (PCA) was applied to assess the various levels of toxic elements as chief causes of variation in the data sets and to find the relation among samples (eye makeup products) and toxic elements (variables). Hierarchical cluster analysis (HCA) was used to explore the grouping of various eye makeup products on the basis of toxic element contents as additional statistics to the output attained by PCA.