Deep eutectic solvent microextraction of lead(II), cobalt(II), nickel(II) and manganese(II) ions for the separation and preconcentration in some oil samples from Turkey prior to their microsampling flame atomic absorption spectrometric determination

A new liquid phase microextraction method based on deep eutectic solvent microextraction was developed for separation and preconcentration of lead, cobalt, nickel and manganese from edible oil samples like sunflower oil, baby oil, trout, waste frying oil and syrup-soaked pastry oil. A choline chloride deep eutectic solvent was used for microextraction. After extraction, analytical concentrations were determined by flame atomic absorption spectrometry. Effects of analytical parameters such as type and volume of deep eutectic solvent, sample volume, and temperature on extraction efficiency of lead, cobalt, nickel and manganese were optimized. The recoveries were generally > 95%. The relative standard deviation (RSD, %, n = 7) of 50 mu g/L of analyte elements was in the range of 0.9-4.3%. Accuracy of presented microextraction method was checked by addition-recovery studies to oil samples. The presented deep eutectic solvent microextraction method was finally applied to edible oil samples and waste oils with different properties for the determination of analyte contents.