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

Abstract

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.

Study of Δ9-tetrahydrocannabinol (THC) and cannabidiol (CBD) extraction FROM dried oral fluid spots (DOFS) and LC–MS/MS detection

“…The first step for DOFS sample preparation is to define the adequate filter paper, its size, its capability of oral fluid absorption and the amount of time needed for complete dryness. Jacques et al ( 2019 ) studied these conditions for Whatman 903® filter paper, defining that a 1.6 cm × 1.6 cm piece of paper would be necessary to absorb 50µL of oral fluid. This sample require a minimum of 2.5 h to dry.…”

“…DOFS sample preparation and extraction procedures were conducted as previously described (Jacques et al 2019 ; Gorziza et al 2020 ).…”

Spectral fingerprinting to evaluate effects of storage conditions on biomolecular structure of filter-dried saliva samples and recovered DNA

“…A faster drying rate is considered beneficial since it shortens the www.nature.com/scientificreports/ duration in the less stable hydrated state during which biomolecules are subject to degradation. The porous structure of filters shortens the drying, whereas applying a stream of dry air further shortens the drying time 39 . In our study, drying of saliva on filters while applying a stream of air resulted in faster drying and allowed for recovery of large quantities of DNA.…”

Dried Spots associado com um método LC-DAD para determinação simultânea de MDMA (ecstasy) e MDA em amostras de fluído oral

“…No entanto, seu alto custo de aquisição e manutenção é limitado para laboratórios forenses que tenham orçamento compatível. Na literatura é possível encontrar diversos métodos desenvolvidos com o MS, ou in tandem (MS/MS) para determinação de MDMA, MDA, e estimulantes do tipoanfetamina em amostras de fluido oral (CONCHEIRO et al, 2008;SERGI et al, 2009;ROSITANO et al, 2016;JACQUES;DOS SANTOS;LIMBERGER, 2019;GORZIZA et al, 2020) e apreendidas (KHAJEAMIRI et al, 2011;COUCHMAN et al, 2019;TEÓFILO et al, 2020), com diversas variações no modo de preparo das amostras, desde simples diluições (dilution-and-shoot) a convencionais extrações líquido-líquido. Os limites de detecção e de quantificação reportados para ambos os analitos podem chegar a níveis na ordem de 0,2 e 0,5 ng mL -1 no fluido oral (WOOD et al, 2003) e até 0,0001 ng mL -1 para o cabelo.…”

“…Fonte: Do Autor. Quanto a fase estacionária, colunas de fase reversa com ligantes fenil, pentafluorofenil, octadecil e octil, e aquelas com apenas sílica foram observados (CONCHEIRO et al, 2005;RAMLI, 2018;JACQUES;DOS SANTOS;LIMBERGER, 2019;DUARTE et al, 2020). Enquanto a C18 e C8 mostram fortes/moderadas interações hidrofóbicas e são utilizadas em diferentes aplicações (considerada "universal"), as baseadas em fenil adicionam ainda as interações π-π e dipolo-dipolo, e podem fornecer seletividade adicional para as separações.…”