Rxi®-5Sil MS (Fused Silica) Columns

This application note by Restek Corporation describes the development of a test method for the analysis of pesticides and mycotoxins in cannabis brownies using the California list.

In this application note, learn a method for GC analysis of derivatized amphetamines using a highly inert Rxi-5Sil MS column and how to obtain low bleed levels, good peak responses, and symmetrical peak shapes.

This application note describes the use of QuEChERS, cartridge SPE cleanup, and GCxGC-TOFMS to analyze potential pesticides found in cannabis. Over 20 states in the U.S. have legalized the use of recreational or medical cannabis because of therapeutic benefits for ailments such as cancer, multiple sclerosis, and ALS. However, medical cannabis patients have no safety assurances for their medication, which could contain harmful levels of pesticide residues. Restek SPE cartridges and selective GC columns allow quick and effective analysis of medical marijuana samples, coupled with excellent pesticide determination accuracy.

In this application note, the QuEChERS sample preparation approach was used to isolate residues prior to analyzing pesticides in tobacco. The cleanup efficacy and pesticide recoveries were evaluated for different formulations of QuEChERS dispersive solid phase extraction (dSPE) cleanup and the more traditional cartridge solid phase extraction (cSPE) cleanup. Comprehensive two-dimensional gas chromatography time-of-flight mass spectrometry (GCxGC-TOFMS) was used to determine pesticide residues in the resulting extracts.

This poster explores GC column and derivatization chemistries that promote increased GCxGC resolving power for metabolomics chemical compounds.

Unlike other prescribed medicines regulated by U.S. FDA, marijuana is a Schedule 1 drug and is illegal on the federal level. As a result, medical cannabis patients have no safety assurances for their medication, which could contain harmful levels of pesticide residues. In order to address matrix complexity, this study combined a simple QuEChERS extraction approach with cartridge SPE (cSPE) cleanup, followed by GCxGC-TOFMS to detect pesticide residues in marijuana samples.

Global concern over the carcinogenic potential of 1,4-dioxane and several nitrosamines has resulted in increased interest in the development of more efficient testing methods for these contaminants in drinking waters. In the U.S., the current methodologies recommended for the analysis of 1,4-dioxane and nitrosamines in drinking waters are Environmental Protection Agency (EPA) Methods 522 and 521, respectively. EPA Method 522 is a relatively simple GC-MS method using electron ionization, while Method 521 requires positive chemical ionization using liquid methanol or acetonitrile reagent gas, along with tandem mass spectrometry. The method described in this application note uses the same coconut charcoal sorbent solid phase extraction cartridges and dichloromethane eluent recommended in EPA Methods 522 and 521 to concentrate 0.50 L water samples to 10 mL extracts.

Large volume splitless injection for gas chromatography typically requires a special injection port, for example, a programmable temperature vaporizer (PTV), but an alternative setup using concurrent solvent recondensation–large volume splitless injection (CSR-LVSI) and a split/splitless injection port has been reported. In this application note from Restek the CSR-LVSI technique, both with and without sample extract concentration, was used to analyze pesticides and brominated flame retardants in drinking water. When extract concentration was eliminated, good linearity and recovery results were obtained while sample preparation time was reduced by over 1 hour. CSR-LVSI was also combined with extract concentration to achieve lower detection limits.

This application note evaluates the efficacy of using a Nutech 8900DS preconcentrator in combination with an analytical system for analysis of VOCs in whole air. Results were assessed based on five criteria outlined for time-integrated, whole air canister sampling in the United States (U.S.) Environmental Protection Agency’s (EPA) Compendium Method TO-15.

Large volume splitless injection for gas chromatography typically requires a special injection port, for example, a programmable temperature vaporizer (PTV), but an alternative setup using concurrent solvent recondensation–large volume splitless injection (CSR-LVSI) and a split/splitless injection port has been reported. In this application note from Restek the CSR-LVSI technique, both with and without sample extract concentration, was used to analyze pesticides and brominated flame retardants in drinking water. When extract concentration was eliminated, good linearity and recovery results were obtained while sample preparation time was reduced by over 1 hour. CSR-LVSI was also combined with extract concentration to achieve lower detection limits.

With a complex portfolio of beverages, snacks, and nutrition, PepsiCo understands the growing complexity of new consumer requirements such as organic foods, as well as staying compliant. Here, Dr. Ellen De Brabander, Senior Vice President, Global R&D, PepsiCo, shares how the company will change the way it works to keep up with this growth, all while ensuring food safety, quality and taste.

In this video Jaap de Zeeuw discusses two new technologies highlighted by Restek at Pittcon 2013. Jaap tells SelectScience how the exceptional inertness and stability of Restek’s Rxi® columns makes them well suited to accurate trace-level analyses. In addition to discussing some of the other key benefits of Rxi® technology, including retention time stability and longer column life, Jaap describes some of the key applications areas such as pesticide, PAH and solvent analysis. Jaap also introduces EZGC™, Restek’s new software for GC method development. Interview filmed by SelectScience at Pittcon 2013.

From vodka aroma profiling to microplastics in water and better beer making, discover our pick of application guides and top tips to help you develop and optimize your analytical methods