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The levels of a common fire retardant found in the blubber of porpoises from UK waters have fallen over the last three years, say environmental researchers. This welcome change has been linked to the closure of a local manufacturing plant and demonstrates the quick response of the aquatic food chain.

A simple, rapid, sensitive and specific method has been used to screen and confirm residues of 13 diuretics belonging to four classes in whole bovine milk.

The contents of an antifungal cream, including the active ingredient, its degradation products and the preservatives, have been measured simultaneously by HPLC. The procedure could be used for monitoring the stability of the drug in cream formulations.

Three proteins commonly encountered in cell cultures have been determined simultaneously in one LC run through two conjoined monolithic disks with different separation characteristics.

A simple, rapid, sensitive and specific method has been used to screen and confirm residues of 13 diuretics belonging to four classes in whole bovine milk.

Read the official report from the 2nd Annual International Conference on Supercritical Fluid Chromatography, which was recently held in Zurich, Switzerland. The conference was organised by the Green Chemistry Group, a non-profit organization dedicated to the advancement of environmentally sustainable chemical research and development throughout the world.

The different varieties of tequila, which are classified according to their aging procedures, can be differentiated by a simple HPLC procedure which looks for a set of five compounds that originate from the oak aging casks.

The passage of PAHs from animal feeds to animal-based human foods can be estimated by measuring their concentrations in the manure of cows, rabbits, pigs and horses. The levels varied from species to species but were declared to be "not alarming" by the Spanish research group.

An HPLC method with a diode array detector was developed for the simultaneous assay of Tinosorb<sup>®</sup>S (bis-ethylhexyloxyphenol methoxyphenyl triazine) with three other sunscreen agents [benzophenone-3, butyl methoxydibenzoylmethane (avobenzone) and ethylhexyl methoxycinnamate] in high protection sunscreen.

Hallucinogenic phenethylamines have been measured in illegal products purchased from a shop and via the internet using an ultrafast HPLC method following conversion to a fluorescent derivative. The method is currently being extended to biofluids.

Czech beers have much higher contents of free amino acids than those brewed in other countries such as Belgium. The main incremented amino acids represent three specific groups, accounting for the specific taste characteristics of the beers.

A new series of ion exchange columns now allows high throughput separations of biomolecules by IEC. As an example for the applicability of TSK-GEL STAT columns in high throughput analysis of biomolecules, the monitoring of PEGylation reactions and other bio-applications is described.<br />

An RP-HPLC method for the determination of gallic acid, pyrogallol, resorcinol and ellagic acid, derived from hydrolysable tannins is reported. It could be used in ruminant nutrition studies to verify the effects of a tannin-rich diet on ruminal fermentation.

Several nicotine metabolites have been measured in wastewater and lake water in Switzerland by LC/MS, as potential markers for the discharge of domestic wastewater and to help in the assessment of their toxicological risk.

Fountain pen inks can be differentiated by ion pairing HPLC, say Chinese researchers, providing a means of checking suspected entries on official documents such as wills and contracts. The predictable ageing of the inks also leads to a method for dating suspicious documents and signatures.

The practical effects of gradient time and flow rate on the peak capacities of a range of analytes of differing molecular weights and physico-chemical properties have been evaluated using ultra high pressure LC instrumentation with sub-2 µm and superficially porous particle phases.

The complex composition of carotenoids in freshly squeezed orange juice has been determined by HPLC using two identical columns in series. This setup enhances the resolution and increases the peak capacity by more than 25% compared with a single column.

Benzoylurea pesticides in tomatoes have been measured by HPLC with detection based on the well-known chemiluminescence reaction of luminol. The method provides a rapid, sensitive and low-cost alternative to existing multiresidue methods that rely on mass spectrometry.

The retention thermodynamics of small, nonpolar solutes on traditional alkyl, polar endcapped, and polar embedded group stationary phases are compared and their retention characteristics are compared using a set of solutes with differing solvatochromic parameters.

A broad range of compounds, including carbohydrates, carboxylic acids, metals and inorganic anions, has been determined in tomatoes by one method in a single, rapid chromatographic run. The contents determined by HPLC-ICP-AES allow differentiation between different tomato cultivars.