An assisted electromembrane extraction method using a novel composite of metal-organic framework and covalent organic framework incorporated into the wall pores of a hollow fiber membrane is presented. The metal-organic framework and covalent organic framework composite combines the high surface area, tunable porosity, and chemical stability of metal-organic framework with the ordered, covalent network of covalent organic framework, providing a synergistic enhancement of extraction performance. In this technique, the composite material dispersed in an organic solvent is immobilized within the porous fiber walls through capillary forces and ultrasonic assistance, improving both the stability and mass-transfer efficiency of the supported liquid membrane. The morphology, structure, and elemental composition of the sorbent are characterized by scanning electron microscopy, energy-dispersive x-ray analysis, and Fourier-transform infrared spectroscopy. Key experimental parameters affecting extraction efficiency are systematically investigated. The developed method demonstrates a linear response range of 2-1000 µg L-1 with limits of detection between 0.6 and 1.5 µg L-1 for selected model drugs. High precision and recoveries are obtained for human plasma and urine samples. Importantly, the approach is not limited to the studied opioids and can be applied to a broader range of ionizable basic pharmaceuticals. Green analytical assessment tools confirm the method's favorable environmental profile.
Sheikhi et al. (Wed,) studied this question.