title: Lead Quantification in Urine Samples of Athletes by Coupling DLLME with UV-Vis Spectrophotometry.
abstract: Urine lead level is one of the most employed measures of lead exposure and risk. The urine samples used in this study were obtained from ten healthy male cyclists. Dispersive liquid-liquid microextraction combined with ultraviolet and visible spectrophotometry was utilized for preconcentration, extraction, and determination of lead in urine samples. Optimization of the independent variables was carried out based on chemometric methods in three steps. According to the screening and optimization study, 133 μL of CCl4(extracting solvent), 1.34 mL ethanol (dispersing solvent), pH 2.0, 0.00 % of salt, and 0.1 % O,O-diethyl dithiophosphoric (chelating agent) were used as the optimum independent variables for microextraction and determination of lead. Under the optimized conditions, R2was 0.9991, and linearity range was 0.01-100 μg L-1. Precision was evaluated in terms of repeatability and intermediate precision, with relative standard deviations being <9.1 and <15.3 %, respectively. The accuracy was estimated using urine samples of cyclists as real samples and it was confirmed. The relative error of ≤5 % was considered significant in the method specificity study. The lead concentration mean for the cyclists was 3.79 μg L-1in urine samples. As a result, the proposed method is a robust technique to quantify lead concentrations higher than 11.6 ng L-1in urine samples.
authors.affiliation: Department of Chemistry, Faculty of Science, Varamin-Pishva Branch, Islamic Azad University, Varamin, 338177489, Iran. hakimfaraji@yahoo.com.
authors.forename: Hakim
authors.identifier: http://orcid.org/0000-0002-1236-0746
authors.initials: H
authors.lastname: Faraji
authors.affiliation: Department of Exercise Physiology, Sport Medicine Research Center, Sport Sciences Research Institute, Tehran, Iran.
authors.forename: Masoumeh
authors.initials: M
authors.lastname: Helalizadeh
mesh_terms: D000328:Adult; D056352:Athletes; D064368:Healthy Volunteers; D006801:Humans; D007854:Lead / Q000652:urine*; D059627:Liquid Phase Microextraction; D008297:Male; D012984:Software; D013056:Spectrophotometry, Ultraviolet; D055815:Young Adult
chemical_list: D007854:Lead
keywords: Chemometrics; Dispersive liquid–liquid microextraction; Lead; UV-Vis spectrophotometry; Urine samples of cyclists; Validation study