On-line sample pre-concentration in capillary electrophoresis: Fundamentals and computational simulation

Abstract

The versatility and simplicity of capillary electrophoresis is widelyknown, thanks to its numerous separation modes, the diversity and types ofmolecules that can be analyzed, i.e. organic and inorganic, of high and lowmolecular weight, ionic or neutral, contained in simple and complex matrices.However, in contrast to all its advantages, the low sensitivity of detection,especially when using absorbance detectors, leads to relatively poor detectionlimits (LODs). The primary aim of this chapter is to describe the fundamentalsof the most straightforward approaches for on-line sample pre-concentration incapillary electrophoresis, utilizing commercially available CE instrumentation,avoiding any modifications to the instrument or sophisticated interfaces. Wealso include numerical simulations for the most important mechanisms in orderto offer the readers a better understanding of the electrolyte dynamics, butalso offering the chance to run cases for themselves for getting even betterexperimental conditions in terms of pre-concentration.