Helium, Hydrogen, or Nitrogen—The Choice is Yours: Unique Rtx®-CLPesticides Column Set Provides Optimal Results for Organochlorine Pesticides GC-Micro-ECD Analysis Using Any Carrier Gas

Author(s): Jason Thomas, Chris English, Jack Cochran, Gary Stidsen
Restek Corporation

Published By: Restek Corporation

Year of Publication: 2014

Link: http://www.restek.com/Technical-Resources/Technical-Library/Environmental/env_EVAR1935-UNV

Abstract: Using an Rtx®-CLPesticides column set is the best strategy for labs considering alternate carrier gases as a way to reduce helium consumption. These columns have a unique selectivity and produce faster results than DB®-CLP1 and DB®-CLP2 columns when using either helium or hydrogen. In addition, only Rtx®-CLPesticides columns can be used with nitrogen, which give labs the freedom to choose the carrier gas option that is best for them.

Analysis of Pesticides in Dietary Supplements: Evaluation of QuEChERS, Cartridge SPE Clean-Up, and Gas Chromatography Time-of-Flight Mass Spectrometry

Author(s): Julie Kowalski, Michelle Misselwitz, Jason Thomas, Jack Cochran

Published By: Agro FOOD INDUSTRY Hi-tech today

Issue: Sept./Oct. Focus on Food Analysis supplement, vol. 22, no. 5

Year of Publication: 2011

Abstract: New requirements for dietary supplements to be manufactured under cGMP regulations have created a need for methods to detect pesticides in these complex, largely botanical products (e.g. vitamins, herbal and botanical pills, etc.) Since dietary supplements contain natural products where pesticides have been employed, methods for pesticide analysis must be evaluated, including sample extraction and cleanup, as well as instrumental techniques such as gas chromatography (GC). The QuEChERS (Quick, Easy, Cheap, Effective, Rugged, and Safe) sample preparation method offers a rapid way to prepare samples for analysis, but dietary supplement extracts can be so complex as to make trace-level pesticide determinations problematic. In this work, we evaluate a method involving QuEChERS extraction and dispersive solid phase extraction (dSPE) cleanup, cartridge SPE (cSPE) cleanup, and GC- time-of-flight mass spectrometry (TOFMS) to detect pesticide residues in dandelion root powder obtained from a dietary supplement vendor.

Large Volume Splitless Injection Using an Unmodified Split/Splitless Inlet and GC-TOFMS for Pesticides and Brominated Flame Retardants

Author(s): Michelle Misselwitz, Jack Cochran

Published By: Restek Corporation

Year of Publication: 2011

Link: http://www.restek.com/Technical-Resources/Technical-Library/Environmental/ev_an1331

Abstract: Concurrent solvent recondensation large volume splitless injection (CSR-LVSI) GC/MS is used here for analyzing pesticides and brominated flame retardants in drinking water based on EPA Method 527. CSR-LVSI allows a time-consuming sample extract concentration step to be eliminated, but can also be used with extract concentration for lower detection limits.

Matrix Effects in Multi-Residue Pesticide Analysis When Using Liquid Chromatography-Tandem Mass Spectrometry

Author(s): Kai Zhang

Published By: Restek Corporation

Year of Publication: 2011

Link:http://www.restek.com/Technical-Resources/Technical-Library/Editorial/mis_0026

Abstract: Matrix effects present a significant challenge to multi-residue pesticide analysis of food samples using LC/MS/MS. In this editorial, Dr. Kai Zhang, of the FDA Center for Food Safety and Applied Nutrition, discusses approaches that minimize matrix effects.

Evaluation of QuECheRS, Cartridge SPE Cleanup, and Gas Chromatography Time-of-Flight Mass Spectrometry for the Analysis of Pesticides in Dietary Supplements

Author(s): Julie Kowalski, Michelle Misselwitz, Jason Thomas, Jack Cochran

Published By: LCGC North America

Year of Publication: 2010

Link: http://www.chromatographyonline.com/lcgc/Articles/Analysis-of-Pesticides-in-Dietary-Supplements/ArticleStandard/Article/detail/697436

Abstract: The FDA is responsible for regulation of dietary supplements as foodstuffs through the 1994 Dietary Supplement Health and Education Act (DSHEA) amendment to the Food Drug and Cosmetic Act (FDCA). Since 2010, manufacturers have been required to adhere to current good manufacturing practices (cGMPs) when producing dietary supplements. Because many dietary supplements are largely derived from botanical sources, they must be tested for pesticide contaminants in order to meet cGMP regulations. As a result of this requirement, labs are working to develop and validate methods, an endeavor that is complicated by the wide range of pesticides and matrices to be tested. Although other researchers have used established methods like those found in the FDA Pesticide Analytical Manual (PAM), we developed a QuEChERS (quick, easy, cheap, effective, rugged, and safe)-based method for analyzing pesticides in dietary supplements.