Reductions in sample pretreatment requirements by using high-performance capillary electrokinetic separation methods

Spectrophotometeric Determination of Cefuroxime Axetil from bulk and in its tablet dosage form

A simple rapid spectrophotometric method has been developed for estimation of cefuroxime axetil from bulk drug and tablet dosage form by using 1-nitroso-2-napthol and sodium hydroxide. The method is based on the formation of yellow-orange coloured complex of drug with 1-nitroso-2-napthol having absorbance maxima at 424 nm. The Beer's law is obeyed in the concentration range of 10-50 mug/ml of the drug but more precisely it obeys in the range of 10- 30 mug/ml. The slope and intercept values are 0.0101 and 0.0838, respectively. Results of analysis of this method were validated statistically and by recovery studies. The method is applied to the marketed tablet formulation. Result of analysis of tablet formulation given as percentage of label claim +/-standard deviation is 99.17+/-1.57. The precision and accuracy was examined by performing recovery studies and was found to be 99.50+/-1.82. Sandell's correlation coefficient is calculated as 0.4434. The developed method is simple, sensitive and reproducible and can be used for routine analysis of cefuroxime axetil from bulk and tablet dosage form.

Determination of drug-related impurities by capillary electrophoresis

The use of capillary electrophoresis (CE) to determine drug-related impurities is becoming established within industrial pharmaceutical analysis laboratories. Increasingly CE is being viewed as an alternative for, and complement to, high-performance liquid chromatography (HPLC). This paper comprehensively reviews the progress of CE in drug impurity determinations subdividing the reports into low pH, high pH and MECC applications. The section covering method performance and validation clearly shows that CE methods are capable of validation in this area and can often give equivalent performance to HPLC methods. Possible benefits of adopting CE for this testing include reductions in costs and improved robustness. Potential developments are covered including the use of electrolyte additives, instrumental developments and the increased implementation of electrochromatography. It is concluded that the current status of CE is sufficiently strong to allow the analyst to view CE as a viable and attractive alternative to HPLC.

Determination of a cyclic guanine monophosphate phosphodiesterase inhibitor (SCH 51866) in rat serum using capillary zone electrophoresis

A capillary zone electrophoretic (CZE) assay was developed for the determination of cis-5,6a,7,8,9,9a-hexahydro-2-[4-(trifluoromethyl)phenylmethyl]-5-methyl - cyclopent[4,5]imidazo[2,1-b]purin-4(3H)-one, SCH 51866 (I), a cyclic guanine monophosphate phosphodiesterase inhibitor, in rat serum using acetonitrile deproteination as a clean-up step before injection. The calibration curve was linear over a serum concentration range of 0.5 to 10 micrograms/ml serum with a correlation coefficient (r) > 0.99. The limit of quantitation (LOQ) was established at 0.5 micrograms/ml. Fifty microliters of serum were used for analysis, which allowed serial bleeding (8 samples) from a single rat to characterize the pharmacokinetic profile of I after either oral or intravenous drug administration. In traditional pharmacokinetic and toxicokinetic studies in rodents, one animal provides only one serum sample since 1 to 2 ml of sample volume is required for chromatographic analysis, resulting in the use of a large number of animals per study. This assay yields a significant reduction in the use of animals, hence providing a large reduction in resources and time in drug discovery and development.

Clinical and forensic applications of capillary electrophoresis

This survey is aimed at giving the readers a short overview of the present state of the art of clinical and forensic applications of capillary electrophoresis. First, the principles associated with electrokinetic capillary separations and instrumentation, sample preparation and solute quantitation are briefly discussed. This is followed by chapters describing the determination of endogenous and exogenous compounds in body fluids and tissue extracts. Finally, a survey of major achievements including reference to fully developed electrokinetic capillary assays is provided. The paper concludes with a brief outlook.

Applications of capillary electrophoresis in pharmaceutical analysis

The role of capillary electrophoresis (CE) in the analysis of peptide/proteins, chiral pharmaceuticals, and other small-molecule drugs has been reviewed. Potential uses of CE range from purity and structural confirmation to a micropreparative technique. Strategies for the prevention of protein wall adsorption include the use of extreme pH values, surface-modified capillaries, and high ionic strengths employing salts of alkali metals or by the addition of zwitterionic surfactants to the background electrolyte. Chiral separations of amino acids and other racemic pharmaceuticals have been achieved by micellar electrokinetic chromatography or by the introduction of cyclodextrins/modified cyclodextrins or other reagents to the running buffer. Applications of capillary electrophoresis to the analysis of small-molecule pharmaceuticals include determinations of drugs and/or excipients in various pharmaceutical preparations and the analysis of miscellaneous pharmaceuticals in standard solutions and biological fluids. The complementary nature of capillary electrophoresis and HPLC, in addition to future expectations of CE in pharmaceutical analysis, is discussed.