Determination of organophosphorus pesticides by gas chromatography with mass spectrometry using a large-volume injection technique after magnetic extraction

作者：Nedaei Maryam; Salehpour Ali Reza; Mozaffari Shahla; Yousefi Seyedeh Mahboobeh; Yousefi Seyed Reza^*

来源：Journal of Separation Science, 2014, 37(17): 2372-2379.

DOI：10.1002/jssc.201400237

• Large volume injection
• Magnetic multiwalled carbon nanotubes
• Organophosphorus pesticides

A fast and efficient method was developed for the extraction and determination of organophosphorus pesticides in water samples. Organophosphorus pesticides were extracted by solid-phase extraction using magnetic multi-walled carbon nanotubes and determined by gas chromatography with ion-trap mass spectrometry. Parameters affecting the extraction were investigated. Under optimum conditions of the method, 10mg magnetic multi-walled carbon nanotubes were added into 10mL sample. After 2min, adsorbent particles settled at the bottom of test tube with a magnet. After removing aqueous supernatant, the analytes were desorbed with acetonitrile. Then, 70 L of acetonitrile phase was injected into the gas chromatography and mass spectrometry system that had an ion-trap analyzer. To achieve high sensitivity, the large-volume-injection technique was used with a programmed temperature vaporization inlet, and the ion-trap mass spectrometer was operated in single ion storage mode. Under the best conditions, the enrichment factors and extraction recoveries were in the range of 113-124 and 74-103%, respectively. The limits of detection were between 3 and 15ng/L, and the relative standard deviations were %26lt; 10%. This method was successfully used for the determination of organophosphorus pesticides in dam water, lagoon water, and river water samples with good reproducibility and recovery.

• 出版日期2014-9