The development of an ultra-sensitive gas chromatographic technique has enabled a team of researchers from the University of Derby, UK, to detect cocaine at picogram levels from forensic swabs. The method, using GC–MS, was developed by forensic science student Sonica Devi to help identify minute traces of cocaine at six phone boxes from around the city of Derby.Samples were taken using a variety of swabs, some wetted with ethanol; wetted with water; and dry swabs to maximize how much cocaine could be lifted from the surfaces of the phone box. The gas chromatograph was able to separate the cocaine from other materials, allowing detection by the mass spectrometer of levels of cocaine as low as fifty picograms.

“By improving the sensitivity of our GC–MS technique we can now see cocaine and other closely related materials down to incredibly low levels, which would not have been possible previously,” said Dr Alan-Shaun Wilkinson, senior lecturer, University of Derby, who supervised Sonica during this project. “This important piece of work opens the door to analysing a whole range of different drug types with similar sensitivities.”

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The development of an ultra-sensitive gas chromatographic technique has enabled a team of researchers from the University of Derby, UK, to detect cocaine at picogram levels from forensic swabs.

Ultra-sensitive cocaine detection

Ten miles off the Californian coastline, at the bottom of the Santa Barbara channel, domes rise from the Pacific Ocean floor. A paper published on-line in the journal 

 identified these as a series of unusual underwater volcanoes.

“They’re larger than a football-field-long and as tall as a six-storey building,” says David Valentine, a geoscientist at UCSB and the paper’s lead author. “When you ‘fly’ Sentry [an autonomous underwater vehicle] over the sea floor, all the textures are visible of a once-flowing liquid that has solidified in place,” says Valentine. But the volcanoes did not form from lava flow as with typical volcanoes. The sub’s robotic arm broke off a sample of the brittle, black material and the team used mass spectrometry, carbon dating, microscopic fossils and comprehensive, two-dimensional gas chromatography, to determine that the structures are asphalt. They were formed when petroleum flowed from the sea-floor about 30  000–40  000 years ago.

“To me, as an oil-spill chemist, this was very exciting,” said Chris Reddy, a scientist at WHOI and a co-author of the paper. “I got to find out what oil looks like after 35  000 years.” According to Reddy, it looks “incredibly weathered. That means nature had taken away a lot of compounds. These mounds of black material were the last remnants of oil that exploded up from below. To see nature doing this on its own was an unbelievable find.”

Ten miles off the Californian coastline, at the bottom of the Santa Barbara channel, domes rise from the Pacific Ocean floor. A paper published on-line in the journal Nature Geoscience identified these as a series of unusual underwater volcanoes.

Underwater asphalt volcanoes

During the manufacture of biomolecules correct glycosylation is essential for the protein to achieve the correct structure and therapeutic efficacy. This process can be strongly influenced by many environmental factors during cell culture, such as dissolved oxygen, pH, carbon source and temperature. Given the number of possible glycan structures that can attach to a protein, it can be time-consuming to identify and quantify them all. This is why Ireland’s National Institute for Bioprocessing Research and Training (NIBRT) and Waters have announced a collaboration that will create the first database for glycan analysis by UPLC. Expected to be available in 2011, NIBRT will develop, maintain and license the database while Waters and NIBRT will co-market it worldwide.

“By combining our know-how in separations and glycan analysis with NIBRT’s expertise in glycobiology we can make fast and accurate glycosylation analysis a reality for the makers of biotherapeutics,” said Dr Jeff Mazzeo, director of biopharmaceutical business operations at Waters, in a statement. “Our goal is to simplify and introduce more certainty into the process of analyzing glycans and making quality biomolecules.”

Ireland?s National Institute for Bioprocessing Research and Training (NIBRT) and Waters have announced a collaboration that will create the first database for glycan analysis by UPLC.

Glycan Database

As stem cells mature they change to form all the different cells that our bodies use. Control of this process could give doctors the tools to meet the needs of many patients with terrible conditions, such as Parkinson’s disease and spinal injuries. By using a metabolomic approach, a group of researchers have described some key differences between stem cells and mature cells as well as metabolites associated with the transition between the two.

 the study used LC–MS to analyse the stem cells’ metabolome and found 60 previously unidentified metabolites associated with the cell progression. “The study reveals an astounding cellular strategy,” commented Oscar Yanes, one of the researchers. “The capacity of embryonic stem cells to generate a whole spectrum of cell types characteristic of different tissues is mirrored at the metabolic level.”

The team suggests that the stem cells’ metabolome allows them to react to in vivo oxidative processes such as inflammation. Supporting this theory, the researchers found that by chemically blocking the oxidative processes, they were able to prevent stem cells’ normal progress into mature heart and nerve cells. Conversely, when specific oxidized metabolites were introduced downstream into the culture, stem cell differentiation was promoted.

By using a metabolomic approach, a group of researchers have described some key differences between stem cells and mature cells as well as metabolites associated with the transition between the two.

A stem cells' metabolome

This article aims to demonstrate a novel accelerated method development approach using a Design of Experiments based Quality by Design (QbD) methodology to develop HPLC and/or UPLC methods optimized for performance and robustness to ensure success in final method validation and ultimately in method transfer.

Regular Article

This article aims to demonstrate a novel accelerated method development approach to develop HPLC and/or UPLC methods

An Automated Workflow for Accelerated Development of a Robust LC Method within a QbD Framework

Chromatographic method development is a significant challenge in analytical chemistry. The chromatographer is asked to find an appropriate compromise between the often conflicting goals of resolution, robustness and run time. The problem of method development is typically divided into two stages. The first stage is the determination of the basic system on which development will proceed (type of chromatography, column choice etc.). The second stage is the optimization of continuous parameters (especially gradient and temperature) within that method space.

Traditionally, the first selection stage is based on a combination of the experience of the method development chromatographer and a limited number of screening experiments. The second stage is usually based on systematic optimization, commonly with software modelling. Software tools for optimization of separations have matured to the point where their use has become commonplace. More recently, software has also begun to be applied to the first stage of method development enabling chromatographers to select more suitable systems for optimization based on characteristics of the compounds of interest rather than by trial-and-error. However, there are many cases where systematic screening is impractical, especially when a method is not intended to become an organizational asset but rather will only be applied a few times. In these cases, the objective is usually to find an adequate method as fast as possible. When some or all of the chemical structures in the mixture are known with a high degree of confidence, it is feasible to perform selection between several “generic” methods based on chemical structures. This article will describe a new system for fast, effective selection between generic methods based on retention time prediction.

Prediction systems for chromatographic retention times.

Structure-based Prediction of Retention Times for Chromatography

This month Incognito reflects on his own laboratory’s strategies for column care and shares their working practices for increasing the longevity of each column and preventing degradation.

This month Incognito reflects on his own laboratory's strategies for column care and shares their working practices for increasing the longevity of each column and preventing degradation.