LCGC Europe-09-01-2006

The fundamental aim of any computerized system validation should be to define its intended use and then test it to demonstrate that it complies with specification.

The gradient linearity and step tests are two of the most useful performance tests that can be made for a liquid chromatography (LC) system. These check the linearity of gradient generation and the accuracy of mobile phase proportioning. These tests, and examples of problems detected as a result of these tests, have been the subject of at least seven "LC Troubleshooting" columns over the last 18 years.1–7 We strongly recommend that every LC system undergo these tests at least on an annual basis, and preferably semiannually. When a new and different example of a problem detected by these tests is discovered, it is hard to bypass the opportunity to share it with our readers. So this month, you get yet another example of how an LC system can fail.

If cyclohexane is mixed with even low amounts of other solvents, the melting pressure increases remarkably.

Capillary extraction (CEx) is used to study the solventless in-tube extraction of naphthalene, acenaphthene, phenanthrene, fluoranthene, chrysene, benzo(a)pyrene and coronene in aqueous samples prepared by analyte spiking into clean waters or, as an alternative, by using the generator–column method of sample preparation. Analysis of laden extractors is conveniently performed by high-resolution gas chromatography (GC), with a flameionization detector (FID). Extraction set-ups and main extraction variables are investigated from a practical point of view. For 2- to 4-ring polycyclic aromatic hydrocarbons (PAHs), equilibrium times are within a few minutes, analytical sensitivity is in the parts-per-billion (ppb) range and reproducibility is better than 10% relative standard deviation (RSD) (n = 6). Coronene behaviour is unique and presumably determined by extreme hydrophobicity and thus very negligible aqueous solubility: in-tube extraction of coronene seems possible only if starting from oversaturated..

Applied Biosystems has joined the Genographic Project as a supporting sponsor for the generation of one of the world's largest databases of information, which will reveal the sources of humankind's diversity. The company has signed a multi-year agreement to provide laboratory research equipment and services to each of the ten participating global research centres. The terms of the agreement were not disclosed.

An experimental design can be considered as a series of experiments that, in general, are defined a priori and allow the influence of a predefined number of factors in a predefined number of experiments to be evaluated.

Now there's light in the "black hole" - of a brief case. German-based international leather and bag specialist BREE has created the first illuminated business handbag with Smart Surface Technology. Bree put their trust in innovative solutions. They say, "We had been toying with the idea of illuminating the dark insides of handbags for quite some time, but lacked an elegant solution which not only met our traditionally high demands with regard to style and function, but was also technically feasible."