Exploring the potential of fabric phase sorptive extraction in postmortem toxicology: Green analysis of pheniramine in a forensic case of its fatal intoxication

Abstract

Sample preparation is vital in postmortem toxicology to extract and purify analytes from complex matrices. Challenges like interfering substances and limited sample quantity can be overcome with effective preparation, ensuring accurate results. Hence, a simple, sustainable, affordable, and high-throughput method using fabric phase sorptive extraction (FPSE) - gas chromatography - mass spectrometry (GC–MS) was developed for pheniramine (PHN) analysis in postmortem biological samples (blood and liver). FPSE extraction efficiency was optimized by studying factors like membrane type, stirring time and speed, back-extraction solvent, sample pH, and ionic strength. The optimized method was validated following SWGTOX guidelines for linearity, precision, sensitivity, recovery, matrix effect, stability, and other relevant parameters. The method exhibited linearity in the range of 0.1–10 µg mL−1 for blood and 0.1–10 µg g−1 for liver samples under optimal conditions. The limit of quantification (LOQ) was 0.066 µg mL−1 and 0.073 µg g−1 for PHN in blood and liver, respectively. Intra-day and inter-day precision were < 5.8% and < 9.8%, respectively. Recovery and accuracy ranged from 74 to 80% and 95–100%, respectively. Real autopsy samples were analyzed using this method, compared to conventional solid-phase extraction (SPE), demonstrating its effectiveness. Additionally, the environmental impact and sustainability were assessed using ComplexGAPI and Analytical Eco-Scale tools. The FPSE-GC–MS method showed superior performance, marking a notable advancement in postmortem toxicology sample preparation. To the best of our knowledge, this is the first application of FPSE in the analysis of postmortem tissue samples. In conclusion, FPSE-GC–MS method offers a simple, sustainable, and affordable approach to sample preparation for postmortem forensic samples, overcoming challenges such as interfering substances and limited sample quantity. These advantages of FPSE make it a promising alternative to traditional methods, positions it as a significant advancement in the field, poised to shape the future of sample preparation in forensic toxicology.