Magnetic carbon nanotubes modified with 1,4-diazabicyclo[2.2.2] octane are a viable sorbent for extraction of selective serotonin reuptake inhibitors

Abstract

Carbon nanotubes were modified with magnetite nanoparticles, and 1,4-diazabicyclo[2.2.2]octane (DABCO) was then covalently attached to their surface. The resulting material is shown to be a viable sorbent for the preconcentration of the selective serotonin reuptake inhibitors citalopram, sertraline, fluvoxamine and fluoxetine via ultrasound-assisted magnetic solid phase extraction. The effects of pH value, sorbent dosage, eluent volume and salt concentration were optimized by central composite design and desirability function. The drugs were quantified by HPLC with UV detection. Detection limits are as low as 0.2, 0.25, 0.3, and 0.5 ng mL−1 for citalopram, sertraline, fluvoxamine and fluoxetine, respectively. The intra-day precisions (RSDs) are 91%. The sorbent can be reused 12 times without a noticeable decrease in extraction efficiency.