Application Notes

The automated derivatization of fatty acids (FAs) was performed with the Agilent 7696A Sample Prep WorkBench. Since free fatty acids show tailing in gas chromatography, transformation of fatty acids into fatty acid methyl esters (FAMEs) is widely used.

This application note describes the use of triggered Multiple Reaction Monitoring (tMRM) for the analysis of pesticide residues applied to chamomile and ginger extracts. The analysis is performed using the Agilent 1290 LC system coupled to a 6460 Triple Quadrupole LC/MS with tMRM acquisition.

Polychlorinated dibenzo-p-dioxins (PCDD) and polychlorinated dibenzofurans (PCDF) are fat-soluble, highly toxic, ubiquitous environmental contaminants found at trace levels in all foodstuffs and animal feed.

Chemical contaminants that are released into the marine environment may be ingested (absorbed) by fish and shellfish and thus become introduced into the human food chain.

Wine is a beverage produced and consumed throughout the world and is a highly valued commodity. Its classification and authenticity can be very important.

Whether the goal is food safety, ensuring quality or establishing provenance, measuring the trace element content of foods and beverages that we all consume is of paramount importance.

More than 1000 pesticides are currently used worldwide in the treatment of soil and crops. Many countries have established allowable levels of those pesticides in food to protect consumers. While these maximum residue levels (MRLs) vary, the default tolerance is 10 parts per billion (ppb).

A GC–MS analyser is described that is reported to substantially expand the workable application range of a classic catalyst contaminants analyser. The use of FS/SIM mode permits identification of unknown contaminants in combination with reliable quantification at trace and ultratrace amounts.

Phenomenex Application Note

Describes the preparation of a reversed-phase monolithic column with an optimized porous structure to separate intact proteins using LC–MS.

Thermo Scientific Application Note

Erythropoietin protein (EPO) is a glycoprotein hormone found in plasma. It is a cytokine for erythrocyte (red blood cell) precursors in the bone marrow.

A new 3.6 µm 100 Å HPLC–UHPLC column (Aeris PEPTIDE) has been introduced that is specifically designed to improve separations of peptide and peptide mapping applications.

The purpose of this study is to determine how the Direct-to-GC vial concentrator tube and the DryVap ® Concentrator System can optimize the recoveries for both low and high boiling point semi-volatile compounds.

Liposomes are made of lipid bilayers and are often used in drug delivery by encapsulating the core with therapeutic drugs. During liposome research, formulation, manufacturing, and quality control, it is of great importance to monitor liposome size and encapsulation.

U.S. EPA Method 531.2 describes the determination of widely used carbamate pesticides in raw surface water using HPLC with fluorescence detection following postcolumn derivatization, which enhances method sensitivity and selectivity as compared to UV absorbance detection.

Size exclusion chromatography (SEC) is a simple HPLC technique used for the molecular weight (MW) distribution analysis of polymers. Several manufacturers provide SEC columns with different base materials and various pore sizes to cover a wide range of polymer analysis.

Simultaneous HPLC analysis of neurotransmitters can be challenging due to the similarity of their structures.

A liquid chromatography tandem mass spectrometry method for enalapril and enalaprilat from human plasma has been developed using Thermo Scientific SOLA cartridges. Sample preparation is fast, efficient, and reproducible giving excellent recovery levels for each compound.

The paralytic shellfish toxins are a group of 18 secondary metabolites deposited in bivalve mollusks by dinoflagelates. Dinoflagelate blooms are seasonal, occurring during warm months.

Microwave assisted extraction (MAE) offers significant benefits over traditional soxhlet extraction for dioxins and furans determination from environmental samples including higher sample throughput, time savings, reduced solvent and great reproducibility.

The determination of common inorganic anions and cations in drinking water is important due to the toxicity of anions (e.g., fluoride, nitrite, and nitrate) and secondary contaminants (e.g., chloride and sulfate) which can affect the water's aesthetics.

A simple screening method for Pyrethroid insecticides in sediment samples is described. Electron impact ionization (EI) with tandem MS-MS in combination with programmed temperature vaporization injection (PTV) were used in order to obtain excellent specificity and low limits of detection.

Omega-3 and -6 fatty acids are essential compounds required for normal growth. Omega-3 consumption is purported to have a number of health benefits, e.g., cancer prevention, cardiovascular disease prevention, and improved immune function. Although both omega-3 and -6 fatty acids can give rise to eicosanoid-signaling molecules (prostaglandins, prostacyclins, thromboxanes, and leukotrienes), the omega-6 eicosanoids are generally proinflammatory. A person's diet requires a balance of omega fatty acids at suitable levels.

A new widepore core-shell HPLC–UHPLC column (aeris WIDEPORE) has been introduced that is specifically designed to improve protein separations.

GCxGC-TOFMS provided a comprehensive analysis of tobacco smoke. Individual smoke constituents across several target compound classes were extracted, chromatographically resolved, then identified and quantified with mass spectral detection.

Over the last decade the use of Pharmaceuticals and Personal Care Products (PPCPs) has doubled in the United States. As a result, PPCPs have entered the environment through both human activity and as by-products from manufacturing, agricultural activities, medical use and veterinarian facilities.

Volatile organic compounds (VOCs) in soil were rapidly extracted and concentrated using solid phase microextraction (SPME) followed by on-site analysis and identification with the TRIDION-9 portable gas chromatograph – toroidal ion trap mass spectrometer (GC-TMS). 37 VOCs were resolved and analyzed quickly in under 3 min.

Shale gas reservoirs, such as the Marcellus shale reserve in Pennsylvania and Barnett shale reserve in Texas are a growing source of natural gas in the United States.

Using a novel new-design monolithic silica column (Chromolith? HighResolution RP-18e), fast, high resolution separations were achieved for various drug mixtures without the high pressures characteristic of modern particulate technology.