Magnetic multi-walled carbon nanotube poly(styrene-co-divinylbenzene) for propranolol extraction and separation by capillary electrophoresis

Abstract

Aim: The preparation of magnetic multi-walled carbon nanotube poly(styrene-co-divinylbenzene) for propranolol magnetic solid-phase extraction is described. Materials & methods: A study comparing propranolol adsorption and desorption was performed with only magnetic multi-walled carbon nanotubes, and different poly(styrene-co-divinylbenzene) with and without magnetic multi-walled carbon nanotubes. Enantiomeric separation of propranolol took place by cyclodextrin-modified capillary electrophoresis and the method was validated in spiked human urine samples. Results: Recovery values raised when styrene/divinylbenzene millimoles ratio was 19.57:15.80. Enrichment factors increased up to approximately 100, detection limits were 13.8 and 10.5 ng ml−1 for R- and S-propranolol respectively, quantitation limits were 46.0 and 34.8 ng ml−1 for R- and S-propranolol respectively, recoveries from spiked samples ranged from 90.9 to 109.0%, and relative standard deviations were <6.3%. Conclusion: This methodology was proven to be more effective than classical solid-phase extraction strategies and may be applied to other kind of biological samples.