Quantitative 31P NMR for Simultaneous Trace Analysis of Organophosphorus Pesticides in Aqueous Media Using the Stir Bar Sorptive Extraction Method

• Published in: Journal of applied spectroscopy 2016, Vol.83 (4), p.717-721
• Main Authors: Ansari, S., Talebpour, Z., Molaabasi, F., Bijanzadeh, H. R., Khazaeli, S.
• Format: Article
• Language: English
• Subjects: Analytical Chemistry; Aqueous solutions; Atomic/Molecular Structure and Spectra; Correlation coefficients; Design factors; NMR; Nuclear magnetic resonance; Pesticides; Physics; Physics and Astronomy; Public health; Quality control; Water sampling
• ISSN: 0021-9037; 1573-8647
• DOI: 10.1007/s10812-016-0353-7

The analysis of pesticides in water samples is of primary concern for quality control laboratories due to the toxicity of these compounds and their associated public health risk. A novel analytical method based on stir bar sorptive extraction (SBSE), followed by 31 P quantitative nuclear magnetic resonance ( 31 P QNMR), has been developed for simultaneously monitoring and determining four organophosphorus pesticides (OPPs) in aqueous media. The effects of factors on the extraction efficiency of OPPs were investigated using a Draper–Lin small composite design. An optimal sample volume of 4.2 mL, extraction time of 96 min, extraction temperature of 42°C, and desorption time of 11 min were obtained. The results showed reasonable linearity ranges for all pesticides with correlation coefficients greater than 0.9920. The limit of quantification (LOQ) ranged from 0.1 to 2.60 mg/L, and the recoveries of spiked river water samples were from 82 to 94% with relative standard deviation (RSD) values less than 4%. The results show that this method is simple, selective, rapid, and can be applied to other sample matrices.