Microwave-assisted extraction and determination of dicyandiamide residue in infant formula samples by liquid chromatography-tandem mass spectrometry

Abstract

A simple, precise, accurate, and validated liquid chromatography-tandem mass spectrometry (LC-MS/MS) method was developed for the determination of dicyandiamide residue in infant formula samples. Following microwave-assisted extraction with 5% formic acid and clean-up on a Sep-Pak AC-2 SPE cartridge, samples were separated on a ZIC-HILIC HPLC column (150. ×. 2.1. mm i.d., 5-μm film thickness; Merck KGaA, Darmstadt, Germany) with 20. m. M ammonium acetate solution-acetonitrile as mobile phase at a flow rate of 0.25. mL/min. A linear calibration curve was obtained in the concentration range from 1.0 to 50. ng/mL. Infant formula samples were fortified with dicyandiamide at 3 levels, producing average recovery yields of 83.6 to 95.7%. The limits of detection and quantification of dicyandiamide were 3 and 10. μg/kg, respectively. Due to its simplicity and accuracy, the straightforward method is particularly suitable for routine dicyandiamide detection. © 2013 American Dairy Science Association.