Development and Validation of a Method Using Dried Oral Fluid Spot to Determine Drugs of Abuse

• Published in: Journal of forensic sciences Vol. 64; no. 6; pp. 1906 - 1912
• Main Authors: Jacques, Ana Laura Bemvenuti, Santos, Maíra Kerpel dos, Limberger, Renata Pereira
• Format: Journal Article
• Language: English
• Published: United States Wiley Subscription Services, Inc 01.11.2019
• Subjects: Acetonitrile; analytic sample preparation methods; analytical chemistry techniques; Chromatography, Liquid; Desiccation; dried oral fluid spot; Drug abuse; forensic science; forensic toxicology; Forensic Toxicology - methods; Humans; Illicit Drugs - analysis; investigative techniques; Ions; Linearity; Liquid chromatography; Mass Spectrometry; Narcotics; Saliva - chemistry; Selectivity; Stability analysis; substance abuse detection; Substance Abuse Detection - methods; Substance-Related Disorders - diagnosis; Toxicology; forensic toxicology; investigative techniques; analytic sample preparation methods; analytical chemistry techniques; dried oral fluid spot; forensic science; substance abuse detection
• ISSN: 0022-1198; 1556-4029
• DOI: 10.1111/1556-4029.14112

A liquid chromatography–mass spectrometry method using dried oral fluid spots was developed and validated for the simultaneous quantification of cocaine, benzoylecgonine, cocaethylene, amphetamine, and 3,4‐methylenedioxymethamphetamine. The oral fluid was applied to a Whatman 903 grade paper and submitted to a drying time of 2.5 h. The extraction procedure was optimized by chemometric approach using simplex centroid design. Spots were extracted with a mixture of acetonitrile, buffer, and methanol. Calibration curves covered a linear concentration range of 40–500 ng/mL. Validation parameters of linearity, precision, accuracy, selectivity, carryover, matrix effects, and stability were evaluated and showed satisfactory results. Spot homogeneity was also satisfactory, with less than 15% of deviation from nominal concentration. Spot volume did not influence accuracy when less than 100 μL of the sample was applied to the spot. The validation of the proposed method suggests a potential application in different scenarios in toxicology.