Extraction induced by emulsion breaking
The extraction of polar and/or metal traces from oily samples is an analytical challenging task due to the nature of the sample matrix. Casella et al. proposed, in 2010, the extraction induced by emulsion breaking technique which faced up this challenge with high success (1). This technique is based on the formation of a stable emulsion between the oily sample (diesel, oil etc.) and an aqueous phase that contains a surfactant. The surfactant promotes the emulsification of both phases favoring their contact and therefore, making easier the transference of the analytes from the non-polar to the polar phase. After the extraction, the emulsion should be broken, usually by centrifugation, in order to allow phase’s separation and the final analysis of the aqueous phase. In a recent article, accepted for publication in Talanta, the same authors have proposed a similar approach for the determination of Cu, Fe and Mn in used lubricating oils (2). This determination is quite important si...