Oxidized multiwalled carbon nanotubes for quantitative determination of cationic surfactants in water samples using atmospheric pressure matrix-assisted laser desorption/ionization mass spectrometry

摘要

Oxidized multiwalled carbon nanotubes(O-MWCNT)are used as preconcentrating probes for the quantitative determination of cationic surfactants(CS~+)in water samples using atmospheric pressure matrix-assisted laser desorption/ionization mass spectrometry(AP-MALDI-MS).The method is based on the electrostatic interactions of positively charged CS~+ with the negatively charged O-MWCNT for the preconcentration and isolation of analytes from sample solutions.The O-MWCNT/AP-MALDI-MS is performed for the determination of CS~+ in river-and waste-water samples.The optimum extraction efficiency of CS~+ is observed for 7min of contact time at 1.0 mg dosage of O-MWCNT at pH 7.0.The acceptable relative recovery percentage in water sample is obtained in the range 90.5-97.8% with relative standard deviation(R.S.D.)<14.5%.The results suggested that the newly proposed method is rapid,accurate and effective and could be successfully applied for the enrichment and quantitative determination of CS~+ in water samples.