Magnetic restricted-access carbon nanotubes for SPME to determine cannabinoids in plasma samples by UHPLC-MS/MS

This manuscript describes the development of magnetic restricted-access carbon nanotubes (M-RACNTs) for use as SPME sorbent to determine cannabidiol (CBD) and delta-9-tetrahydrocannabinol (THC) in human plasma samples by UHPLC-MS/MS. The adsorptive phase was immobilized on an SPME device by electromagnetic interactions between the M-RACNTs and a cylindrical neodymium magnet (3-mm diameter x 8-mm height) attached to a stainless-steel rod (3-mm diameter x 40-mm height). The M-RACNTs were synthesized by incorporating Fe