Development and Application of Online Solid Phase Extraction Liquid Chromatography Mass Spectrometry in Cannabinoids and Their Metabolites Analysis in Cancer Patients Using Cannabis Oil Extract

Abstract

        The level of cannabis active compounds in patients, who receiving medical cannabis from medical cannabis clinics, are essential information for determining effective and safe dosing for each individual patient. This study aimed to develop and validate an Online SPE LC-MS technique for the quantification of cannabinoids and their metabolites ∆⁹-tetrahydrocannabinol (THC), cannabidiol (CBD), 11-hydroxy-∆⁹-tetrahydrocannabinol (11-OH-THC) and 11-nor-9-carboxy- tetrahydrocannabinol (THC-COOH) in plasma specimens collected from cancer patients who participating in a clinical research program to evaluate the efficacy of Thai medical marijuana products. The method was optimized to obtain an acceptable accuracy, precision and minimization of sample-preparation requirements. Full method validation was performed to establish its suitability as a standard operating procedure. The validated method demonstrated a working range of 10–100 ng/mL with correlation coefficients r > 0.995. The limits of detection (LOD) and lower limits of quantification (LLOQ) were 5 ng/mL and 10 ng/mL, respectively. Precision, expressed as percent coefficient of variation (%CV), ranged from 1.3% to 11.6%, while accuracy, assessed as percent relative difference (%RD), ranged from 0.1% to 16.7%. On account of its minimal sample-volume requirement, the method is particularly suitable for clinical research involving vulnerable patient populations in whom blood collection must be limited. The developed online SPE LC-MS method was successfully applied to the analysis of 54 plasma samples from 18 patients. Furthermore, this method has been accredited under the international standard ISO/IEC 17025:2017, affirming its technical competence and adherence to globally recognized quality requirements.