Accelerated solvent extraction for gas chromatographic analysis of nicotine and cotinine in meconium samples

Adverse effects associated with smoking during pregnancy are well documented. Although self-report surveys on drug consumption during pregnancy have been improved with new interviewing techniques, underreporting is still a concern. Therefore, a series of biological markers and specimens to diagnose fetal exposure to tobacco have been studied. In the present study, an analytical method was developed to detect nicotine and cotinine (the main nicotine metabolite) in meconium samples. Accelerated solvent extraction (ASE) followed by solid-phase extraction (SPE) were used as sample preparation techniques. The analytes were detected by gas-chromatography with nitrogen-phosphorus detection. The limits of detection were 3.0 and 30 ng/g for cotinine and nicotine, respectively. The method showed good linearity (r(2) > 0.98) in the concentration range studied (LOQ-500 ng/g). The intraday precision, given by the RSD of the method, was less than 15% for cotinine and nicotine. The method proved to be fast, practical, and sensitive. Smaller volumes of organic solvents are necessary compared to other chromatographic methods published in the scientific literature. This is the first report in which ASE was used as sample preparation technique in methods to detect xenobiotics in meconium.