Multiresidue Pesticides Analysis in Ayurvedic Churna

Keywords food safety traditional herbal medicine spices liquid/liquid extraction timed-SRM 

The sample preparation involves the extraction of 15 g powdered sample of Avipittakara churna with 15 mL acetonitrile containing 1% acetic acid in the presence of 3g magnesium sulfate, 1.5 g sodium acetate and 10 g NaCl. The supernatant (1 mL) was collected after centrifugation, and a dispersive clean-up was performed using 200 mg PSA and 10 mg GCB. The extract was centrifuged at 10 000 rpm for 5 min. Three microlitre of the supernatant was injected for analysis. For recovery and validation studies 15 g of a confirmed blank churna matrix is fortified with appropriate quantities of a pesticide standard mixture. 

The analytical method comprises a triple quadrupole GC-MS/MS system with liquid autosampler. The gas chromatograph is equipped with a temperature programmable PTV injector for splitless injection. The separation is performed using a 5% phenyl phase column of standard dimensions. After a short dispersive SPE clean-up the acetonitrile extract is directly injected after centrifugation. The Thermo Scientific TraceFinder software with compound database of pesticides was used for method setup and data processing (The Pesticides Compound Database, 2014). 

For all pesticide compounds two SRM transitions have been chosen for the MRM acquisition method. The first transition was used for quantitation, the second transition for confirmation by checking the ion intensity ratio during data processing, see Table 4.15. 

Sample material Ayurvedic churna, herbs, spices 

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