Gyula Vigh, professor of chemistry and holder of the Gradipore Chair of Separation Science at Texas A&M University, has been selected as the 2011 recipient of the Hungarian Society for Separation Sciences (HSSS) Halász Medal Award recognizing research excellence in the separation sciences.

Named in honour of István Halász, who was a leading scientist in gas chromatography and a pioneer in liquid chromatography, the award commends researchers for outstanding achievements in or contributions to the study of separation science. The award will be presented at a ceremony during the 36th International Symposium on High Performance Liquid Phase Separations and Related Techniques, on 19–23 June at the Budapest Congress and World Trade Centre in Budapest, Hungary.

Vigh’s research focuses on analytical chemistry — specifically electrophoresis. His lab is currently investigating isoelectric trapping of ampholytic substances within a device to achieve separation — a vital tool in the purification process for a wide variety of substances, from medications to proteins, in a host of applications.

In addition to being presented with the award during the symposium, Vigh is scheduled to present a plenary lecture explaining his lab’s technique entitled, “A New Preparative-Scale Isoelectrophoretic Trapping Device: Design, Construction and First Characterization.”

To learn more about Vigh and his research, visit 

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Halász Medal

The N-methylcarbamates and the N-methylcarbamoximes are among the most widely used pesticides in agriculture. Dionex has announced an improved HPLC method for the determination of these chemicals. 

These pesticides may create health problems, including issues impacting the central nervous and reproductive systems. As a result, concerns over the presence of carbamate residues in water, crops, and food products have promoted increased awareness and testing for these compounds. 

The improved method focuses on the determination of carbamates in rice, potato and corn as specified in AOAC Method 2007.01 and European Union standard EN 15662, 2008. 

Application Note 272: Faster Yet Sensitive Determination of N-Methylcarbamates in Rice, Potato and Corn by HPLC

 is reported to demonstrate accurate results using the company’s UltiMate 3000 HPLC system with an Acclaim Carbamate column and detection performed using an FLD-3400RS fluorescence detector.

The N-methylcarbamates and the N-methylcarbamoximes are among the most widely used pesticides in agriculture. Dionex has announced an improved HPLC method for the determination of these chemicals.

Pesticide analysis

Researchers in Japan have found a way to separate nanometre-sized particles in a water-filled capillary using a laser-induced shockwave. The study, published in 

 describes the microscopic chromatographic technique, termed laser-induced shockwave chromatography, that the authors say shows advantages compared with normal chromatography, particularly in terms of its speed and applicability to sticky and absorbing polymers.

To perform the separation, a single laser pulse is fired at a point within the water-filled capillary, turning the water within into super-hot plasma.  The plasma expands quickly, sending a shockwave along the capillary and carrying nearby particles with it. The distance the shockwave carries the particles depends on their sizes; larger particles gain more momentum from the blast and so travel further.

The technique was tested on proteins, their aggregates and inorganic nanoparticles and found it was effective on particles between 9–300 kDa. Using it on nanoparticles, the researchers were able to separate particles differing in size by only a few nanometres.

The study concludes that the main advantage of this technique is its speed: The shockwave travels through the capillary in a fraction of a second, moving the particles less than a millimetre, which the study claims would make it suitable for lab-on-a-chip devices.

1. T. Nagahara, N. Ichinose and S. Nakamura, 

Researchers in Japan have found a way to separate nanometre-sized particles in a water-filled capillary using a laser-induced shockwave.

KA-POW!

Unlike wine and whisky, beer tastes best when consumed fresh. After 6–12 months in storage, beer develops an unpleasant, bitter aftertaste. A study to identify the key substances that cause this bitter taste has been published in the 

Journal of Agricultural and Food Chemistry

Using quantitative LC–MS–MS profiling, a variety of commercial beers were analysed before and after storage. The researchers were able to identify 56 hop-derived sensometabolites for the first time, and were able to gain an insight into the transformation of the bitter compounds during storage. 

The study concluded that the time and temperature dependant proton-catalysed cyclization of trans-iso-α-acids was the predominant reaction that led to the formation of harsh tasting tri- and tetracyclic compounds during storage. Due to their stability they have been suggested as indicator molecules to monitor the ageing status of beer. The study concludes that it offers “a scientific basis for a knowledge‑based optimization of the beer bitter taste by controlling the initial pH value of the beer by technological means and by keeping the temperature as low as possible during storage of the final beverage.’

Unlike wine and whisky, beer tastes best when consumed fresh. After 6-12 months in storage, beer develops an unpleasant, bitter aftertaste. A study to identify the key substances that cause this bitter taste has been published in the Journal of Agricultural and Food Chemistry.

Shelf life

Chromatographers are generating more data than ever, as they adopt automation tools and faster methods to keep up with demands for increased productivity and for higher confidence in results. Managing all the data has become a major challenge because there is not enough time to scrutinize every chromatogram and result. Analysts need efficient ways to view the big picture, to spot significant items within the larger data set and to quickly analyse specific items that need closer examination.

A natural and effective solution is to present data graphically. Graphical representations allow large amounts of data to be presented in a compact format, facilitate comparison and make anomalies easy to detect. For example, the MiniPlots featured in the Chromeleon 7.1 chromatography data system (CDS) software presents a detailed miniature thumbnail image of each chromatogram in an injection sequence or query result. The user can scan dozens of chromatograms quickly and immediately spot any that differ in number of peaks, peak size or shape, background profile and so on.

The interactive charting capabilities provide chemists with powerful new tools for analysing chromatography data more efficiently.

Interactive Charts: A Powerful New Tool for Understanding Chromatography Data

Incognito draws some similarities about how the advances in car technology have mirrored those in HPLC systems. Whilst the end products may look better, perform better and be more reliable than previous ones this progress is at the loss in knowledge about how the car or instrument actually works and how it can be maintained.

Incognito draws similarities between advances in car technology and HPLC systems. Better end products have come at the cost of knowledge about how it actually works and can be maintained.

My First Motor Car...

The goal of non-targeted cross-sample analysis is to discover salient chemical characteristics from multiple samples. Applications of non-targeted cross-sample analysis include sample classification, quality control, chemical fingerprinting and biomarker discovery. Non-targeted cross-sample analysis should distinguish and reliably characterize all chemical constituents in each sample, correctly match the corresponding features that characterize each constituent in different samples, and recognize the most significant characteristics or patterns between or among samples. Comprehensive two‑dimensional gas chromatography (GC×GC) is a powerful technology for separating complex samples and therefore is well suited for non-targeted analysis. GC×GC data is information-rich but is also large and complex, making the analytical tasks of extracting and matching features and then recognizing salient patterns challenging. This review surveys some of the varied approaches that researchers have applied to these difficult problems.

Comprehensive two-dimensional gas chromatography is a powerful technology for separating complex samples and therefore is well suited for non-targeted analysis.