Simultaneous accelerated solvent extraction and hydrolysis of 11-nor-Δ9-tetrahydrocannabinol-9-carboxylic acid glucuronide in meconium samples for gas chromatography-mass spectrometry analysis

Cannabis misuse during pregnancy is associated with severe impacts on the mother and baby health, such as newborn low birth weight, growth restriction, pre-term birth, neurobehavioral and developmental deficits. In most of the cases, drug abuse is omitted or denied by the mothers. Thus, toxicological analyzes using maternal-fetal matrices takes place as a suitable tool to assess drug use. Herein, meconium was the chosen matrix to evaluate cannabis exposure through identification and quantification of 11-nor-Δ9-tetrahydrocannabinol-9-carboxylic (THCCOOH). Accelerated solvent extraction (ASE) was applied for sample preparation technique to simultaneously extract and hydrolyze conjugated THCCOOH from meconium, followed by a solid-phase extraction (SPE) procedure. The method was developed and validated for gas chromatography-mass spectrometry (GC-MS), reaching hydrolysis efficiency of 98%. Limits of detection (LOD) and quantification (LOQ) were, respectively, 5 and 10 ng/g. The range of linearity was LOQ to 500 ng/g. Inter and intra-batch coefficients of variation were <8.4% for all concentration levels. Accuracy was in 101.7-108.9% range. Recovery was on average 60.3%. Carryover effect was not observed. The procedure was applied in six meconium samples from babies whose mothers were drug users and showed satisfactory performance to confirm fetal cannabis exposure.