All News
UHPSFC–MS Analysis of Complex Lipid Samples
July 9th 2015Researchers at the University of Pardubice in the Czech Republic have developed a high-throughput ultrahigh-performance supercritical fluid chromatography–mass spectrometry (UHPSFC–MS) method that can analyze lipidomic samples in as little as 6 min.
Effective Cleanup of Fat Containing Samples in the Analysis of Contaminant Residues
July 7th 2015High fat content of foods has been a problem when analyzing samples for nonpolar contaminants such as pesticides, PCBs, and PAHs. Extraction methods for these compounds tend to generate samples that are highly contaminated with fatty matrix, causing a number of problems with the subsequent chromatographic analysis. Traditional cleanup techniques, such as gel permeation chromatography (GPC) and normal phase column chromatography can be very effective, but are often expensive and time consuming. In this seminar, we will present an alternative approach to the cleanup of fats using a novel zirconia-based family of sorbents, for both QuEChERS (dispersive SPE) and traditional cartridge SPE.
Eight Steps to Better Results from Solid-Phase Extraction
July 7th 2015If you use SPE in your work, then most likely it’s very important to the success of your applications and it’s proper implementation will be key to the performance of your analyses. However, SPE protocols are “variable in quality” (I’ve been as I kind as I can there!) and this variability appears to come from some common issues, misunderstandings and, frankly, ignorance of the mechanisms which are in play.
10th Balaton Symposium on High-Performance Separation Methods
July 1st 2015The 10th Balaton Symposium on High‑Performance Separation Methods will be held on 2–4 September 2015 at the Hotel Azúr in Siófok, Hungary. The biannual Balaton Symposium has grown to be one of the most important events of the separation science field in central Europe, bringing together separation scientists and friends from all over the world. The symposium is designed to discuss the latest issues, current requirements, and technological challenges faced in the present and the future. Twenty years after the first Balaton Symposium, the Hungarian Society for Separation Sciences continues the tradition.
Using Compact Mass Spectrometry for Detection and Quantitation of Cannabis-Related Compounds
July 1st 2015Compact mass spectrometry, in combination with suitable sample introduction techniques-such as the atmospheric solids analysis probe, thin-layer chromatography, and classical liquid chromatography techniques-can be used effectively for the detection and quantification of cannabinoids and pesticides in cannabis-related material and contraband.
Why and How to Avoid Ionic Contamination in Water Used for LC–MS Analyses
July 1st 2015Ionic contaminants in the water used in UHPLC analyses with MS detection method lead to adduct formation and reduced analytical signals because of ion suppression. In MS, the preferred ion type is the protonated molecular ion, especially in peptide analysis, since the partially mobile proton charge enables more meaningful fragmentation analysis, as compared to a sodiated peptide ion. Moreover, the occurrence of protonated analyte signals indicates that solvents and reagents, as well as the MS instrument used in analyses, are clean and do not contribute any contaminating cationic components to the analytical process. In the experiments presented here, it was observed that the signal intensities of the protonated species decreased as the sodium ion concentration in the water increased. This was accompanied by an increase in the intensity of sodiated adducts.
Comparison of Compounds in Bourbon Vanilla Extract and Vanilla Flavour
July 1st 2015This application note presents a gradient method using a core–shell column for the determination of various substances in Bourbon vanilla extracts as well as in natural and artificial vanilla flavours. The aim is to compare the ingredients to achieve proof of the authenticity of Bourbon vanilla. By applying the Knauer AZURA Analytical system, a very short analysis time and low eluent consumption could be achieved. The high speed and reliability of the method makes it well-suited for routine analyses in food control.
Detection of Aflatoxins in Milk at Picogram Levels Using SPE and LC–MS–MS
July 1st 2015Aflatoxins (B1, B2, G1, and G2) are naturally occurring mycotoxins produced by fungi on agricultural crops. They are classified as carcinogenic and can pose a significant risk to human health if consumed. Although aflatoxin B1 is the most potent carcinogen, the main concern in milk is its hydroxylated metabolite, aflatoxin M1. To ensure the safety of milk, the US FDA established a tolerance of 0.5 µg/kg for aflatoxin M1 in milk, while the EU set a limit of 0.05 µg/kg in raw milk and 0.025 µg/kg in infant formula. A simple and effective method using polymeric solid-phase extaction (SPE) and liquid chromatography coupled to tandem mass spectrometry (LC–MS–MS) is presented for the analysis of aflatoxins in milk at the low concentrations required.
Fast and Simple Determination of Free Amino Acids in Milk
July 1st 2015Amino acids are of vital importance for human life. They serve as transport or storage media for metabolic pathways. Amino acids are components of protein-containing foods such as milk and milk products. Eight amino acids are thought to be essential for humans, meaning that they must be absorbed from foods containing animal proteins or a suitable combination of plant proteins, because the human body can’t synthesize them. Determination of the composition and content of amino acids in milk products is therefore an important measure in ensuring quality and nutritional value.
Million Metabolome Project, an ambitious milestone for Exposome Research
June 23rd 2015Ultra high resolution, accurate mass (UHRAM) mass spectrometry, based on the Thermo ScientificTM OrbitrapTM technology, is a powerful new approach to high throughput screening and quantitation in complex sample matrices. To learn more about how UHRAM is used in the Million Metabolome Project, an ambitious milestone for Exposome Research, LCGC talked with Dean Jones of Emory University.
GC Temperature Programming—10 Things You Absolutely Need to Know
June 19th 2015Temperature affects not only retention but also relative retention in gas chromatography (GC) and therefore, when we change temperature, we also change the selectivity of the separation. This is true as we alter the isothermal separation temperature, but also as we change the slope of the temperature program gradient.
