Fortify or Calibrate for 203 Pesticides by GC-MS/MS With This Single Restek® CRM Kit

GC-MS/MS Multiresidue Pesticide StandardsGC-MS/MS is the technique of choice for analyzing pesticide residues in many fruits, vegetables, botanicals, and herbals like tea, ginseng, ginger, Echinacea, and dietary supplements. And Restek’s new GC-MS/MS pesticide reference standards kit contains over two hundred compounds pulled from the food safety lists of the FDA, USDA, and other global agencies.

This stock, comprehensive set joins the 204-compound LC-MS/MS kit in Restek’s lineup of world-class certified reference materials (CRMs) for multiresidue pesticide analysis. Both kits are formulated and grouped for maximum long-term stability. Every ampul is quantitatively tested to confirm composition, and detailed support documentation is provided. Restek also supplies an optimized multiresidue pesticide method free of charge; the downloadable XLS file includes conditions and transition tables.

No more long nights or weekends in the lab. No more custom standards. Restek’s food safety experts can help you make quick work of getting the accurate results you need. Combine this ready-made multiresidue pesticide standards kit with Restek’s internal standards, Rxi®-5ms GC columns, Q-sep® QuEChERS sample preparation, inlet liners, and more.

ChromSoc Food Analysis Conference to Feature Talk by Jaap de Zeeuw

On April 9, 2014, in collaboration with The Chromatographic Society (ChromSoc), Syngenta Research Labs will host “Separating the Wheat from the Chaff; Advances in Natural Product Analysis” at their Jealotts Hill Research Centre in Bracknell, Berkshire, UK. The focus of this conference is the chromatographic and mass spectrometric analysis of foods, vegetables, and natural products. Restek’s International GC Specialist Jaap de Zeeuw will join Professor Pat Sandra (Gent), Dr. Paul Russell (Unilever), Dr. Robin Clery (Givaudan), Dr. Geoffrey Kite (Kew), and other noted industry experts in a full day of valuable presentations.

Considerations for Improved Measurement of Traces in Food Matrices by Minimizing the Injection Bandwidth Using Normal and Large Volume Splitless Injection
Jaap de Zeeuw (presenter)
Restek Corporation

Jaap de Zeeuw

Jaap de Zeeuw

Abstract: In GC, the efficiency of a capillary can only be exploited if the analytes injected are focused as a narrow band. Using a split injection, this is relatively easy as the injection is fast. If trace analysis is required, a bigger sample volume has to be injected. To inject a larger sample, one needs to eliminate the impact of the solvent.

It is possible to remove the solvent via concentration techniques, but this will cause extra sample preparation time. Easier is to inject a larger amount onto the column. Special injection techniques have been developed to introduce larger sample volumes. One of the most used techniques is the splitless technique. In this technique, the sample is introduced in a hot liner with the split line closed. The whole content of the liner is transferred into the column, which takes between 20 and 60 seconds. To get a focused band, one uses the solvent effect by setting the oven temperature about 20 °C below the BP of the solvent. Components will focus here and a narrow band is created.

The focusing will only happen if the solvent used is compatible with the surface polarity of the stationary phase. If there is no compatibility, the solvent will form droplets and multiple injection bands can be formed. The same challenge is observed when larger volumes are introduced. The use of a retention gap helps for generating a focused band, not only when solvent is entering the column, but also when solvent and column phase are not compatible. The retention gap was found to be extremely helpful in operating the large volume splitless injection technique known as CSR-LVSI. This acronym stands for “concurrent solvent recondensation – large volume splitless injection.” With this technique, it is possible to get a focused band while injecting volumes up to 100 µL in standard split/splitless injection systems.

Standard split/splitless systems for injection of larger volumes, avoiding the use of (expensive) PTV-type injection systems and methods, are relatively easy to set up once the process of band-focusing is understood.

Restek has been a leader in the chromatographic analysis of food for over 25 years, so we are proud to be a participant in what is sure to be an informative and worthwhile event. In addition to the long list of distinguished speakers, attendees will also have access to an exhibition of leading manufacturers and suppliers, including Thames Restek UK.

To view the schedule of talks and to register, visit today.

QuEChERS: Beyond the Basics

Author(s): Julie Kowalski and Jack Cochran
Restek Corporation 

Published By: Separation Science

Issue: vol. 5, issue 4

Year of Publication: 2013


For the full print issue, visit

Abstract: QuEChERS is a sample preparation approach that was designed to be easy, cheap but effective and rugged at the same time. It is most often used for pesticide residue analysis but its beneficial features have assisted it in branching to other fields such as environment, bioanalytical and clinical. QuEChERS was originally designed for fruits and vegetables and proven to work especially well for high water content fruits and vegetables (>80 %) with slightly acid pH (5–6). However, there are commodities that don’t fit into this food type. Adjustments to the typical QuEChERS procedures extend its usage outside of these typical or easy commodities. Common examples include very acidic food like citrus fruits and fatty foods like avocado, milk and oils.