Stereoselective separation and determination of triadimefon and triadimenol in wheat, straw, and soil by liquid chromatography–tandem mass spectrometry

Abstract

A sensitive and rapid analytical method was developed for simultaneous determination of triadimefon (TF) and triadimenol (TN) stereoisomers in wheat, straw, and soil by liquid chromatography coupled with triple quadrupole mass spectrometry (LC-MS/MS). The direct enantioseparation of TF and TN was performed on a Lux cellulose-1 column packed with cellulose-tris-(3,5-dimethylphenylcarbamate). The effects of mobile-phase composition on the separation were investigated and stereoisomeric elution orders were confirmed with a polarimeter detector. The pesticides were extracted from samples with acetonitrile and cleaned up by solid-phase extraction or activated carbon. Based on the developed stereoselective LC-MS/MS method, for TF and TN stereoisomers, good linearities were obtained over the concentration range of 0.003-4 mg/L; recoveries were 84.2-102.7% in wheat, 84.0-104.0% in straw, and 85.2-106.8% in soil at spiked concentrations of 0.007-2.0 mg/kg; intra-day and inter-day assay precisions were below 12.2%. Limits of detection (LODs) and limits of quantification (LOQs) in wheat, straw, and soil were 0.001-0.005 mg/kg and 0.007-0.02 mg/kg, respectively. Finally, the method was successfully applied to detect TF and TN stereoisomers in wheat, straw, and soil samples from residual trials in farm.

Stereoselective metabolism, distribution, and bioaccumulation brof triadimefon and triadimenol in lizards

“…TN-A is 80 percent of the total triadimenol, while TN-B is about 20 percent. Liang et al (2012Liang et al ( , 2013 The stereoselective HPLC-MS/MS method described in this investigation was validated for simultaneous separation and determination of TF and TN stereoisomers in lizards.…”

“…Racemic TF (99.55 percent) and TN (99.1 percent), analytical standards of TN-A (racemate of RS-and SR-enantiomer, 99.9 percent purity) and TN-B (racemate of RR-and SS-enantiomer, 99.9 percent purity) were kindly provided by College of Science, China Agricultural University (Beijing, China) (Liang et al, 2012). Stock solutions of TF and TN were prepared in methanol (HPLC grade, Dikma, USA) at 1000 mg/L and kept in dark at À 20 1C.…”

Direct Enantioseparation of Nitrogen‐heterocyclic Pesticides on Amylose‐tris‐(5‐chloro‐2‐methylphenylcarbamate) by Reversed‐Phase High‐Performance Liquid Chromatography

“…Most compounds cannot get the linear relations between ln(a) or ln(R s ) and 1/T on amylose-based CSPs, but those can be done on cellulose-based CSPs. 13 In this article, the stereoisomeric optical rotation signals of all pesticides were identified with ORD at 426 nm in different mobile phase systems, and all results were summarized in Tables 1 and 2. 15,26 Generally, the change of solvent percentage in mobile phase would not change enantiomeric optical rotation signals, but the change of solvent types would lead to reversed signals.…”

The Development and Application of Cellulose-Based Stationary Phases in Stereoselective Separation of Chiral Pesticides

“…This is very helpful to prepare optically pure enantiomer of polar chiral compounds and obtain more enantiomer in a shorter time. Additionally, the use of HPLC in the reversed phase can easily be connected in tandem with mass spectrometry, which makes it possible to establish more sensitive and more efficient analytical methods for enantioselective studies of chiral pesticides [40][41][42]. No …”