title: A rapid analytical method based on microwave-assisted extraction for the determination of drugs of abuse in vitreous humor.
abstract: Robust and simple validated analytical methods are required in postmortem toxicology to confirm immunoassay screening analysis of drugs of abuse. In this work, microwave-assisted extraction (MAE) was evaluated as an alternative method for extraction of target compounds such as cocaine, benzoylecgonine, cocaethylene, morphine, codeine, 6-monoacetylmorphine, methadone, and 2-ethylidene-1,5-dimethyl-3,3-diphenylpyrrolidine from vitreous humor. The MAE procedure parameters, namely, extraction temperature, time, and solvent volume, were optimized using a central composite design and applying desirability functions. The optimal conditions for extraction were 80 °C, 8 min, and 15 mL of dichloromethane solvent. The MAE-high-performance liquid chromatography-diode-array detection method was validated, showing its capability for the detection of concentrations in the range from 33 to 76 ng mL(-1) and recoveries in the range from 87 to 99.3% for all drugs. The MAE-based method was tested for 15 vitreous humor samples from forensic cases and its performance was compared with that of a solid-phase extraction method previously developed by our group. In general, better recovery and precision were achieved with the use of the MAE-based procedure.
authors.affiliation: Institute of Legal Medicine, Forensic Toxicology Service, Faculty of Medicine, C/ San Francisco s/n, 15782 Santiago de Compostela, Spain. puri.fernandez@usc.es
authors.forename: Purificación
authors.initials: P
authors.lastname: Fernández
authors.forename: Santiago
authors.initials: S
authors.lastname: Seoane
authors.forename: Cristina
authors.initials: C
authors.lastname: Vázquez
authors.forename: Ana M
authors.initials: AM
authors.lastname: Bermejo
authors.forename: Antonia M
authors.initials: AM
authors.lastname: Carro
authors.forename: Rosa A
authors.initials: RA
authors.lastname: Lorenzo
mesh_terms: D002851:Chromatography, High Pressure Liquid; D006801:Humans; D013287:Illicit Drugs / Q000032:analysis*; D008872:Microwaves; D009022:Morphine Derivatives / Q000032:analysis*; D052616:Solid Phase Extraction; D012997:Solvents; D019966:Substance-Related Disorders; D014822:Vitreous Body / Q000737:chemistry* / Q000187:drug effects*
chemical_list: D013287:Illicit Drugs; D009022:Morphine Derivatives; D012997:Solvents