A simple, inexpensive, non-enzymatic microwave-assisted method for determining bisphenol-A in urine in the form of trimethylsilyl derivative by GC/MS with single quadrupole.

Humans are widely exposed to bisphenol-A (BPA) owing to the ubiquitous use of this chemical in consumer products. Increasing attention is paid to the effect of BPA, because it has the hormone-like structure and it can potentially adversely affect. A simple, efficient, cheap analytical procedure for quantitative determining the analyte is reported in this paper. The suggested method includes the sample preparation based on a double liquid-liquid microextraction combined with non-enzymatic acidic hydrolysis under the influence of microwave radiation of the BPA conjugates with glucuronic and phosphorous acids followed by trimethylsilylation and GC/MS detection. The detection and quantification limits of BPA in the human urine sample are 0.3 and 1 ng/mL respectively. The calibration curve for this analyte is linear with a correlation coefficient of > 0.99 in the range of 1-50 ng/ml. Method recoveries were between 86 % and 110 %, while repeatability was below 10 %. The method was satisfactorily applied to the determination of target compounds in human urine samples from 20 randomly selected individuals. The detection frequency in urines was 40 %. The maximum detected concentration of BPA was 479 ng/mL. The proposed non-enzymatic method is simple, fast, inexpensive and suitable for the determination of BPA in urine samples in the framework of biomonitoring studies and bioanalytical analyses.