Monitoring Pb in Aqueous Samples by Using Low Density Solvent on Air-Assisted Dispersive Liquid–Liquid Microextraction Coupled with UV–Vis Spectrophotometry

In this study, AA-DLLME combined with UV–Vis spectrophotometry was developed for pre-concentration, microextraction and determination of lead in aqueous samples. Optimization of the independent variables was carried out according to chemometric methods in three steps. According to the screening and optimization study, 86 μL of 1-undecanol (extracting solvent), 12 times syringe pumps, pH 2.0, 0.00% of salt and 0.1% DDTP (chelating agent) were chosen as the optimum independent variables for microextraction and determination of lead. Under the optimized conditions, R = 0.9994, and linearity range was 0.01–100 µg mL −1 . LOD and LOQ were 3.4 and 11.6 ng mL −1 , respectively. The method was applied for analysis of real water samples, such as tap, mineral, river and waste water.