An advanced application of the quantitative structure–activity relationship concept in electrokinetic chromatography of metal complexes

Capillary electrophoretic methods in the development of metal-based therapeutics and diagnostics: new methodology and applications

In recent years, capillary electrophoresis (CE) has matured to a standard method in medicinal inorganic chemistry. More and more steps of the drug discovery process are followed by CE. However, not only the number of applications has steadily increased but also the variety of used methodology has significantly broadened and, as compared to a few years ago, a wider scope of separation modes and hyphenated systems has been used. Herein, a summary of the newly utilized CE methods and their applications in metallodrug research in the timeframe 2006-2011 is presented, following related reviews from 2003 and 2007 (Electrophoresis, 2003, 24, 2023-2037; Electrophoresis 2007, 28, 3436-3446). Areas covered include impurity profiling, quality control of pharmaceutical formulations, lipophilicity estimation, interactions between metallodrugs and proteins or nucleotides, and characterization and also quantification of metabolites in biological matrices and real-world samples.

Capillary electrophoretic separation and characterizations of CdSe quantum dots

We have developed a capillary electrophoresis method to characterize the QD surface ligand interactions with various surfactant systems. The method was demonstrated with 2–5 nm CdSe nanoparticles surface-passivated with trioctylphosphine oxide (TOPO). Water solubility was accomplished by surfactant-assisted phase transfer via an oil-in-water microemulsion using either cationic, anionic, or non-ionic surfactants. Interaction between the QD surface ligand (TOPO) and the alkyl chain of the surfactant molecule produces a complex and dynamic surface coating that can be characterized through manipulation of CE separation buffer composition and capillary surface modification. Additional characterization of the QD surface ligand interactions with surfactants was accomplished by UV-VIS spectroscopy, photoluminescence, and TEM. It is anticipated that studies such as these will elucidate the dynamics of QD surface ligand modifications for use in sensors.

Recent advances in the methodology, optimisation and application of MEEKC

MEEKC is an electrodriven separation technique. Oil-in-water microemulsions (MEs) and to a lesser extent water-in-oil MEs have been used in MEEKC as BGEs to achieve separation of a diverse range of solutes. The more common (oil-in-water) MEs are composed of nanometre-sized droplets of oil suspended in an aqueous buffer. Interfacial tension between the oil and aqueous phase is reduced close to zero by the presence of a surfactant and a co-surfactant. MEEKC is capable of providing fast and efficient separations for a wide range of acidic, basic and neutral, water-soluble and -insoluble compounds. This review details the advances in MEEKC-based separations from the period 2006 to 2008. Areas covered include online sample concentration, chiral separation, suppressed electroosmosis MEEKC, MEEKC-MS, and the use of MEEKC in predicting migration behaviour and solute characteristics. A fundamental introduction to MEEKC, along with the presentation and discussion of recent applications is also included.