In this work, we developed an improved, indirect GC-MS method for the analysis of 3-MCPD and glycidyl esters by evaluating different inlets (PTV and split/splitless) and injection modes (split vs. splitless).
This fast, simple LC-MS/MS workflow for the direct analysis of polar pesticides in spinach provides good retention and peak shape over hundreds of matrix injections on a Raptor Polar X column.
More reliable GC analysis of glycerides in edible oils can be obtained using Rxi-65TG columns because they offer higher thermal stability and lower bleed than typical 65-type columns.
Government regulations in California require the cannabis industry to test edible products for an extensive list of pesticides and mycotoxins. Here, an effective workflow for this complex analysis was developed in brownies, and optimization strategies are detailed in order to provide a starting point for similar matrices. Both LC-MS/MS and GC-MS/MS were employed and excellent results for LOQ, linearity, accuracy, and precision were attained for all the target compounds.
Suitable for high-throughput cannabis testing labs, this LC-UV method reliably separates 19 cannabinoids in a quick, 10-minute analysis. Using only 3 mL of acetonitrile per run, labs can significantly decrease solvent use and the associated costs by adopting this procedure.
This method for acrylamide analysis in food provides faster analysis times and meets EN 16618.2015 system suitability requirements longer compared to porous graphitized carbon column methods.
(PDF - 3195kB)
Restek’s new Rxi-65TG column offers best-in-class thermal stability up to 370 ˚C, making it the top choice for the analysis of triglycerides in edible oils. With the lowest bleed on the market for 65-type columns, Rxi-65TG columns consistently produce quality separations with less interference from bleed and fewer column changes.
Dietary supplements, which are consumed worldwide, are made from various botanical ingredients. To be safe from pesticides exposure, residual pesticides must be monitored by chromatographic instrumentation. Issues arise, however, due to the fact these botanical samples are dried and cause large interferences in the chromatography. This study shows that the modified QuEChERS method combined with GC-MS/MS achieves consistent pesticides monitoring in botanical ingredients.
Pyrrolizidine alkaloid analysis is time consuming, with a typical run time of 15 minutes, and the acid digestion step can shorten analytical column lifetime. In contrast, this analysis using an acid-resistant Raptor ARC-18 column eluted the final compound in just 3.2 minutes with good peak shape and separation.
Restek has been helping cannabis labs establish innovative, cost-effective analytical solutions from the very beginning. We have the GC and LC products and expertise you need today for analyzing potency, terpenes, residual solvents, and pesticide residues. And we are developing the products you’ll need tomorrow for emerging cannabis applications in this fast-growing industry.
The analysis of fatty acids in milk fat is an important test and this challenging matrix was used by Eurofins Analytik GmbH to evaluate the stability of Rt-2560 columns. Consistent retention times and separations were achieved even after 225 injections, demonstrating the column’s robust performance.
Stable isotope dilution assay (SIDA) is a calibration technique that can be used to offset matrix effects. However, care must be given to choosing appropriate internal standards. This article demonstrates the importance of using a labeled internal standard that matches the target analyte for mycotoxin SIDA analysis.
The analysis of 3-MCPD and glycidyl esters using AOCS Cd 29c-13 is time consuming and exposes the GC-MS to harsh derivatization reagents that can limit column lifetime and increase maintenance costs. Here, we optimized the method using split injection, resulting in a time savings of 8 minutes, less damage from derivatization reagents, and the flexibility to use either PTV or split/splitless inlets.
The establishment of a 1 µg/g safety threshold for melamine in infant foods has led to a need for sensitive methods. Here we established GC/MS conditions for highly reproducible analyses and evaluated the effectiveness of both solvent-based and matrix-matched standards. Using this method, melamine and cyanuric acid were reliably detected at and below 1 µg/g in infant formula.
The method developed here provides a fast analysis of mycotoxins in peanut powder. Baseline separation of 12 FDA and EU regulated mycotoxins was achieved in a 5.5 minute analysis (7 minute total cycle time). This method can be applied to different matrices using either matrix-matched calibration or a stable isotope dilution assay. Sample throughput can be greatly increased by the short cycle time for each run.
The analysis of bisphenolic compounds that are used as alternatives to bisphenol A (BPA) is essential for monitoring exposure to and evaluating the safety of these emerging industrial chemicals. The LC-MS/MS method presented here provides excellent chromatographic peak shape and separation for an extensive list of BPA analogues in a fast, 8-minute analysis.
Complex, time-consuming immunoaffinity column sample prep protocols for mycotoxins can be replaced by this simple pass-through SPE sample cleanup. Paired with LC-MS/MS analysis using a Raptor Biphenyl column, excellent chromatographic results were obtained for aflatoxins and ochratoxins at 2 ng/g, providing a high-throughput solution for analyzing mycotoxins in cannabis.
Capillary GC is especially useful for determining total fat content, trans fat content, and total omega-3 polyunsaturated fatty acid content in foods. The choice of capillary column depends on the information required. As shown here, whatever your fatty acid analysis requirements, Restek can provide the consistent-performance analytical columns and reference mixes that will help you to accurately characterize your materials.
Multiresidue pesticides analysis presents many challenges, from extensive lists of chemically diverse analytes to the negative effects of complex matrix components. The optimized chromatographic method described here allows the analysis of hundreds of compounds in as little as 7.5 minutes with a total cycle time under 10 minutes, ensuring fast, accurate sample screening and increased lab productivity.
This simple, isocratic LC-UV analysis of cannabinoids provides complete resolution of 16 cannabinoids, allowing accurate quantitative potency and profile data to be reported. All compounds are separated to baseline in a fast, 9-minute analysis, making this method suitable for high-throughput cannabis testing labs.
The analysis of melamine and related compounds is critical in protecting consumers from adulterated food products. While these highly polar analytes are difficult to retain and accurately quantify on many columns, the Raptor HILIC-Si column and LC-MS/MS method shown here allow quick and complete separations, so melamine and related compounds can be accurately identified and quantified even at residual levels.
Mycotoxin contamination of crops is not only a public health concern, but it also has a huge impact on the global economy. This highly selective LC-MS/MS analysis of 20 mycotoxins in just 9 minutes allows scientists to accurately identify toxins, to monitor food products for contamination, and to support control strategies that prevent economic loss.
Restek has optimized the manufacturing process and implemented a new, application-specific QC testing procedure for all new Rt-2560 columns (cat.# 13198). Here we demonstrate that, Rt-2560 columns produced using the optimized process exhibit excellent performance for both AOAC 996.06 and AOCS Ce 1j-07 FAMEs analysis and meet all method requirements.
Even minor variations in manufacturing processes can potentially have detrimental effects on column-to-column reproducibility. As shown here, Rt-2560 GC columns produced using a newly updated and optimized manufacturing process exhibit high reproducibility and provide consistent performance for detailed cis/trans FAMEs analysis.
Raptor FluoroPhenyl columns perform well in both HILIC and reversed phase modes, giving method developers the flexibility to select the mode that performs best for their specific compounds of interest. Here we use a Raptor Fluorophenyl column in HILIC mode for LC analysis of 4-methylimidazole (4-MEI). This approach provides more retention than reversed phase mode and can be applied to determining 4-MEI levels in caramel colorings to monitor formulations and also in foods and beverages to assess potential exposure.
The use of antibiotics on food-producing animals is a public health and safety concern due to the potential of generating drug-resistant bacteria. A sensitive, efficient, and reliable analytical method for different classes of antibiotics is necessary to meet regulations covering maximum residue limits (MRL) for a variety of animal tissue and food products. The Raptor C18 LC column is the ideal choice for antibiotic residue analysis.
Despite the growing popularity of electronic cigarettes, relatively little work has been done to characterize their vapor. In this study, we developed a quick, simple thermal desorption device for sampling vapor, as well as methods for analyzing vapor and solutions to determine nicotine content (GC-FID) and impurity profiles (GC-MS). This novel approach, which utilizes an Rtx-VMS column, provides detectable levels of volatile organic compounds (VOCs) and semivolatile organic compounds (SVOCs) from a single 40 mL puff.
This application note describes the development of an analytical method for PAHs in tea that allows analysts to more quickly and accurately characterize target PAHs. Sample preparation is based on a modified QuEChERS extraction and solid phase extraction sample cleanup. Both GC-TOFMS and GC-MS/MS techniques were used and analyses were optimized for resolution of isobaric compounds, as well as for maintaining a reasonable analysis time.
As medical marijuana is more frequently prescribed, patient safety must be ensured. Pesticide residue testing is an important part of assuring safe product is dispensed, but analysis can be extremely challenging due to matrix complexity. The use of QuEChERS, cartridge SPE cleanup, and GCxGC-TOFMS as presented here, produces high-quality quantitative data for this difficult analysis.
(PDF - 0kB)
Low-bleed Stabilwax-MS columns produce excellent results for the analysis of trace levels of polar compounds by GC-MS. These columns are ideal for a wide range of polar analytes including FAMEs, flavor compounds, essential oils, solvents, aromatics, acrolein/acrylonitrile, and oxygenated compounds.
(PDF - 0kB)
Glucosinolates with hydrophilic functional groups are very difficult to retain by conventional reversed phase HPLC, and when the functional groups in a sample are diverse, polarity can differ widely, complicating the problem. Until now, reversed phase HPLC with an ion pairing reagent has been the inconvenient, but necessary, approach to these analyses. This 2-page note describes a column and conditions for analyses of glucosinolates, without ion pairing.
We compared the efficacy of dSPE and cSPE cleanup methods for multiresidue pesticide analysis of QuEChERS extracts of finished tobacco products using GCxGC-TOFMS. Cleanup with dSPE tubes containing 7.5 mg of GCB and 25 mg of PSA produced better results than other methods, with average recoveries of 92% and 91% for 500 ppb and 50 ppb fortifications respectively.
(PDF - 0kB)
Separate isobaric polycyclic aromatic hydrocarbons, including priority EFSA PAH4 compounds benz[a]anthracene, chrysene, benzo[b]fluoranthene, and benzo[a]pyrene, easily and accurately on an Rxi-PAH column. Whether you need more resolution or faster analysis, these new GC columns offer the selectivity and efficiency you need for food safety and environmental PAH analysis.
QuEChERS extraction, dSPE cleanup, and GC-TOFMS analysis were used to assess pesticide residue levels in strawberry and spinach from both commercial and Amish growers. Various dSPE sorbent products were compared to determine which were most effective.
Melamine contamination was implicated in a large pet food recall that occurred in 2007 when animals died after eating contaminated pet food. Here, a modified GC/MS method, based on an FDA method, was used to analyze for melamine & related compounds cyanuric acid, ammelide, and ammeline in dry cat food. Analytes were easily identified by retention time matching and mass spectra.
Chromatographic methods for garlic and garlic powder are used by the food and dietary supplement industries to monitor product quality. Here we present a headspace gas chromatography mass spectrometry (HS GC/MS) method for garlic flavor and odor components using an Rxi-5ms column. This method eliminates sample preparation making the bench work simple and fast. The experimental set-up is ideal for both screening analysis and low-level trace analysis.
Quick, Easy, Cheap, Effective, Rugged, and Safe, the QuEChERS ("catchers") method for extracting pesticides from food is based on USDA research and employs a novel dispersive solid phase extraction cleanup (dSPE). QuEChERS methods are convenient, rugged methods that simplify extract cleanup, reduce material costs, and improve sample throughput. Here we demonstrate the effectiveness of QuEChERS sample cleanup using a multiresidue analysis of pesticides on strawberries.
Conditions are established for analyzing both derivatized and underivatized cholesterol on a highly inert Rxi-5ms column. Methods described include both an isothermal analysis for use when interferences are minimal, but sample throughput is critical, and a temperature program for use when separation of analytes from contaminants or interfering compounds is the primary concern. Results for both derivatized and underivatized samples were highly reproducible.
Illegal use of malachite green (MG), an inexpensive fungicide, can allow MG to enter water cycles, where it is easily absorbed by fish tissue, and thus enters the human food supply. Reversed phase HPLC often is used to analyze for MG and its stored metabolite, leucomalachite green. Methods that facilitate detection of both compounds are discussed.
(PDF - 0kB)
Thermal desorption is used extensively for measuring volatile and semivolatile components in foods, flavors, fragrances, and odors. This 28-page publication from Markes International Ltd. presents several key applications.