Micellar Liquid Chromatography: How to Start
September 1st 2008Micellar liquid chromatography (MLC) is a reversed-phase liquid chromatographic mode with a solution of surfactant forming micelles as the mobile phase. The interaction of solutes with the stationary phase coated with surfactant monomers, combined with the increased solubilization capability of micelles, have profound implications with regard to retention, selectivity and efficiency. Practical steps that a chromatographer involved in MLC should consider when developing an analytical procedure are described, including mobile phase preparation, column conditioning and cleaning.
3 μm Particle-Based Chiral Stationary Phases for the Fast and Efficient Resolution of Enantiomers
September 1st 2008The move from conventional particle sizes (5 μm or higher) to smaller diameter packing materials is one of the most attractive approaches to achieve higher separating efficiency. Recently developed 3 μm polysaccharide-derived chiral stationary phases demonstrate characteristics of favourable mass transfer kinetics, high column efficiency and good column permeability. This allows the fast analysis of enantiomers using conventional HPLC instruments.
Extracting Information from Chromatographic Herbal Fingerprints
September 1st 2008Herbs and their extracts are currently being used for preventive and therapeutic goals. Consequently, the identification and quality control of these natural products is becoming increasingly important. Fingerprint chromatography is accepted as an appropriate identification and quality evaluation technique for medicinal herbs. This article reviews the development procedure of a fingerprint and different ways to handle the fingerprint data.
The Application of Capillary Electrophoresis for Vaccine Release and Characterization
September 1st 2008Capillary electrophoresis (CE) is increasingly being used in vaccine analysis. Applications include vaccine quantification, purity assessment, process monitoring, characterization and nucleic acid analysis. CE has been used because it offers advantages over other techniques. Vaccine manufacturers such as Sanofi-Aventis, Merck and Wyeth are actively investigating the use of CE for vaccine analysis. While CE can be considered a mature technique, its application to vaccine release and characterization has been limited. It is difficult to ascertain if its use is expanding because there are still a small amount of publications, but given the inherent advantages of CE and the need for better analytical techniques in vaccine analysis, the application must be growing. This article illustrates some of the uses of CE in vaccine analysis.