LCGC Europe-09-01-2005

This article gives an overview of screening methods for the detection of antimicrobials, including dilution and diffusion methods and bioautography, mainly direct bioautography. The thin-layer chromatography method with direct bioautography was worked out to analyse enrofloxacin and ciprofloxacin residues in milk.

Where the wizard stands behind the curtain working levers.

This article looks at the use of electromigration techniques to determine microorganisms, such as viruses, bacteria and other biologically important macromolecules (erythrocytes), in medical analyses. It was found that electromigration techniques could be used for the identification of several viruses, including the identification of a specific marker for the Hepatitis C virus infection and another for a urinary tract infection. The determination of cell viability and the quality control of probiotics and consumer products that contain active bacteria is also possible using electromigration. Special attention is paid to the modification of capillary wall surfaces using different monomers and the application of monolithic columns to determine active bacteria in pharmaceutical products using capillary electrochromatography (CEC) conditions. This approach represents a new frontier for separation science and the possibility to apply it in medical diagnosis.

Sometimes the mobile phase conditions selected for reversed-phase and ion-pairing methods seem either arbitrary or mysterious.

Emerald expansion

The implementation and validation of a new site-wide chromatography data system for a major active pharmaceutical ingredient custom manufacturer provided the opportunity to map and optimize the GMP and ISO business processes to use electronic signatures effectively. This article describes the process optimization and how it integrates with the validation activities of the system. This overall approach provides substantial business benefits from the use of electronic signatures as evidenced by the savings resulting from process improvement and by the fact that the non-GMP laboratories implemented a similar process to analyse and approve results electronically.