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

A method termed pseudo-stir bar hollow fiber solid/liquid phase microextraction (HF-SLPME) was utilized to extract three -blockersatenolol, metoprolol, and propranololin environmental waters. The extracted -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 -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 -blockers were analyzed at room temperature by high-performance liquid chromatography-fluorescence detection. The results showed that practical pre-concentration factors varied from 25.2822. Under the optimized extraction conditions, the method showed good linearity and low limits of detections, 15.0, 10.0, 1.0 mu gL1 for atenolol, metoprolol, and propranolol, respectively. Relative recovery of -blockers in real water samples were between 89.793.1 for tap water, 88.990.7 for clinical waste water, and 91.293.8 for industrial waste water with RSDs between 0.71.4%.