Simultaneous Determinations of 17 abused drugs and organophosphorus pesticides in human blood by GPC-GCMS

Importance of the Topic

Simultaneous monitoring of illicit drugs and organophosphorus pesticides in blood is critical for forensic investigations, clinical toxicology and compliance testing. This dual analysis streamlines workflows, reduces sample handling and addresses complex biological matrices.

Objectives and Study Overview

The study aimed to establish a fast, reliable method for concurrent quantification of 17 abused drugs and organophosphorus pesticides in human blood. A modified QuEChERS protocol was combined with on-line gel permeation chromatography coupled to gas chromatography–mass spectrometry to achieve efficient cleanup and sensitive detection.

Methodology and Instrumentation

• Sample Preparation: Two milliliters of blood were extracted with acetonitrile, followed by cleanup with PSA, C18 and magnesium sulfate. The supernatant was evaporated and reconstituted in the mobile phase.
• Gel Permeation Chromatography: Cleanup utilized a Shodex CLNpak EV-200 column at 40 C with acetone/cyclohexane (30/70 v/v) at 0.1 mL per minute to remove proteins, lipids and pigments online.
• Gas Chromatography–Mass Spectrometry: Separation was achieved on Rtx-5ms columns with a programmed temperature vaporization injector. The oven was ramped from 82 to 300 C under selected ion monitoring to enhance specificity.

Main Results and Discussion

The method provided baseline separation of all 17 analytes, with calibration exhibiting correlation coefficients above 0.997. Limits of detection ranged from 0.001 to 0.012 mg per liter. Recovery rates between 70 and 115 percent and relative standard deviations below 5 percent were achieved at spiking levels of 0.05 and 0.5 micrograms per milliliter, demonstrating excellent accuracy and precision.

Benefits and Practical Applications

The combined QuEChERS and on-line GPC-GCMS approach offers rapid sample throughput, reduced matrix interferences and reliable quantitation. It is suitable for forensic casework, clinical monitoring of drug exposure and surveillance of pesticide poisoning in biomedical laboratories.

Future Trends and Opportunities

Advancements may include greater automation of cleanup and analysis, integration with high-resolution mass spectrometry for broader screening, miniaturized GPC formats to reduce solvent use and expansion to other classes of chemical contaminants in biological matrices.

Conclusion

The developed protocol delivers a fast, sensitive and robust tool for simultaneous determination of abused drugs and organophosphorus pesticides in blood. Its strong validation parameters and streamlined workflow meet the demands of modern analytical toxicology and hold promise for extended applications.