Uncertainty Analysis of Chlormequat Residue in Fruits by LC–MS–MS

Abstract

A method for determination of chlormequat (CCC) residue in fruits by liquid chromatography-tandem mass spectrometry (LC-MS-MS) was developed. Residue of CCC was extracted from samples with methanol-water (v/v, 1:1) containing 1.0% acetic acid, cleaned up by strong cationic exchange (SCX) cartridge, and then determined by LC-MS-MS. The method showed good linearity over the concentration range 0.002-5.0 mg kg -1 with correlation coefficient above 0.997. The limit of detection (LOD) and limit of quantitation (LOQ) for CCC were 5 9 10 -4 mg kg -1 (S/N = 3) and 0.002 mg kg -1 (S/N = 10), respectively. Recoveries for CCC at three spiked levels (0.025, 0.050, and 0.20 mg kg -1 ) were in the range 80-102%. Estimation of measurement uncertainty was calculated for CCC at the level of 0.025 mg kg -1 in fruits. The results demonstrated that the uncertainty of recovery was the main contribution to the combined standard uncertainty. The relative combined standard uncertainties associated with the method ranged from 11 to 13%, depending on the sample matrices.

A highly sensitive method for simultaneous determination of the quaternary ammonium pesticides chlormequat and mepiquat in pears and potatoes by modified QuEChERS-high performance liquid chromatography-tandem mass spectrometry

“…8,11,[13][14][15][16][17] Although the SPE was sensitive and accurate, the procedure was relatively tedious and time/solventconsuming. 8,11,[13][14][15][16][17] Although the SPE was sensitive and accurate, the procedure was relatively tedious and time/solventconsuming.…”

“…Of the published HPLC-MS or HPLC-MS/MS methods mainly solid phase extraction (SPE) was used for CQ and MQ in various matrices. 8,11,[13][14][15][16][17] Although the SPE was sensitive and accurate, the procedure was relatively tedious and time/solventconsuming. In recent years, a QuEChERS (quick, easy, cheap, effective, rugged, and safe) method which was originally developed by Anastassiades et al 18 in 2003 has been widely accepted for sample preparation in pesticide residue analysis.…”