Pre-concentration and determination of β-blockers using carbon nanotube-assisted pseudo-stirbar hollow fiber solid-/liquid-phase microextraction and high-performance liquid chromatography with fluorescence detection

摘要

A method termed pseudo-stir bar hollow fiber solid/liquid phase microextraction (HF-SLPME) was utilized to extract three β-blockers - atenolol, metoprolol, and propranolol - in environmental waters. The extracted β-blockers were then separated, identified, and quantified by high-performance liquid chromatography with fluorescence detection. In HF-SLPME a porous polypropylene hollow fiber filled with MWCNTs reinforced organic solvent that acts as an analyte trap to pre-concentrate β-blockers from water samples. Both ends of the hollow fiber segment are sealed with magnetic stoppers. This device is placed inside the aqueous feed solution and plays the rule of a pseudo-stir bar. The effective parameters are optimized. The extracted β-blockers were analyzed at room temperature by high-performance liquid chromatography-fluorescence detection. The results showed that practical pre-concentration factors varied from 25.2-822. Under the optimized extraction conditions, the method showed good linearity and low limits of detections, 15.0, 10.0, 1.0 μg L-1 for atenolol, metoprolol, and propranolol, respectively. Relative recovery of β-blockers in real water samples were between 89.7-93.1 for tap water, 88.9-90.7 for clinical waste water, and 91.2-93.8 for industrial waste water with RSDs between 0.7-1.4%.