Lead Quantification in Urine Samples of Athletes by Coupling DLLME with UV-Vis Spectrophotometry
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, R 2 was 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−1 in urine samples. As a result, the proposed method is a robust technique to quantify lead concentrations higher than 11.6 ng L−1 in urine samples.
KeywordsDispersive liquid–liquid microextraction UV-Vis spectrophotometry Chemometrics Validation study Lead Urine samples of cyclists
The authors are gratefully acknowledging the support of this work by the Islamic Azad University, Varamin-Pishva Branch.
Compliance with Ethical Standards
All the participants were informed about the purpose of the study and gave informed consent. Experimental procedures were approved by the Ethics Committee of Islamic Azad University, Varamin-Pishva Branch.
Conflict of Interest
The authors declare that they have no conflict of interest.
All procedures performed in studies involving human participants were in accordance with the ethical standards of the institutional and/or national research committee and with the 1964 Helsinki Declaration and its later amendments or comparable ethical standards.
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