Rotative liquid-liquid microextraction combined with nanodrop-fiber optic-linear array detection spectrophotometry for trace analysis of lead in blood samples

A new combined method including nanodrop- fiber optic-linear array detection spectrophotometry (ND-FO-LADS) and Rotative liquid–liquid microextraction (RLLME) was developed for preconcentration and determination of trace amounts of lead in blood sample. This method is based on the formation of a complex between the lead ions present in a sample and dithizone as the chelating agent and its microextraction into the organic solvent[1]. The remained phase after RLLME was introduced as a single drop in to the nanodrop traycell of fiber optic spectrophotometer. The nanodrop spectrophotometric method can be used to avoid the use of large volumes of reagent solution, and typically requires only a single drop of sample solution to take spectrophotometric measurements[2]. This method is especially suitable for blood, where the availability of the sample is scarce. Under the optimum conditions for 5 mL water sample, the calibration curve was linear in the range of 20-80 ng mL–1 and detection limit was 3.5 ng mL–1. The relative standard deviation was 5.33. The validated method was applied for preconcentration and determination of lead in blood and urine samples. The average recoveries of blood spiked samples were 98.65%. The proposed combined method is simple, rapid, sensitive and environmentally friendly for determining traces of lead in the blood samples.