Assessing the usefulness of solid-phase microextraction (SPME) for methadone and its metabolites analysis in urine samples using HPLC/SPME fibre tips
Majidah Mahmoud AlFahmi
Ministry of Health,Administration of Forensic Services in Taif,Forensic Toxicology Unit
Abstract
Solid-phase microextraction (SPME) has been introduced as a novel, simple andsingle- steptechnique of extracting methadone (MDN), 2-ethylidene-1,5-dimethyl-3,3- diphenylpyrrolidine(EDDP) and 2-ethyl-5-methyl-3,3-diphenyl-1-pyrroline (EMDP) from urine samples. In this study, direct immersion SPME followed by high-performance liquid chromatography with ultraviolet detection (HPLC-UV) was developed to identify methadone and its metabolites.These paration was performed on a Gemini C18 (octadecyl carbonchain) analytical column (150x2.0mm,5µm)and detected by an ultraviolet(UV) detectorat 210 nm. The factors in fluencing the SPME procedure,such as the sample’s pH, fibre coating type, salt addition and desorption solvent type were optimised. The best conditions were obtained with a C18 coating at a pH of 11, NaCl 15% and ethyl acetate.
The recoveries of MDN, EDDP and EMDP under optimum conditions were 90.8%,89.3% and 86.5 %, respectively. The calibration curves for urine samples showed good linearity under optimum conditions (R² range 0.9983–0.9988) in a concentration range of 0.025–4 µg/mL for the analytes, using hydrocodone as the internal standard. All samples were analyzed using validated method. The selectivityof this method was evaluated and provided clean chromatograms with no interference in the analysis. Finally, the results show that the novel SPME fibre tips have relatively high extraction efficiency for methadone and its metabolites.
How to Cite
AlFahmi, M. M., Assessing the usefulness of solid-phase microextraction (SPME) for methadone and its metabolites analysis in urine samples using HPLC/SPME fibre tips.STJ,2024, 1,62
https://doi.org/10.70957/uqu.edu.sa/s.toxicology.s/stj.2024.1.7
Received: 07 November 2024, Accepted: 27 January 2025, Published: 09 February 2025
Copyright: © 2024 by the authors. Licensee Umm Al-Qura University, Makkah, Saudi Arabia