Extraction of THC and metabolites including 11-nor-9-carboxy-Δ9-THC glucuronide from urine using ISOLUTE SLE+ prior to LC-MS/MS analysis

This application note describes the simultaneous extraction of THC and its major metabolites, including 11-nor-9-carboxy-Δ9-THC glucuronide, from urine using supported liquid extraction (ISOLUTE SLE+ in both plate and column formats) prior to analysis by LC-MS/MS. Effective and efficient ISOLUTE SLE+ protocols optimized for sample volumes of either 200 uL or 1 mL are described. Due to the pH sensitivity of glucuronidated metabolites and the necessity to avoid any hydrolysis back to parent analytes due to harsh pH conditions, sample pre-treatment using ion pair reagents was investigated. The simple sample preparation procedure delivers clean extracts and high analyte recoveries with RSDs of <10% for all analytes.