Separation of oligopeptides, nucleobases, nucleosides and nucleotides using capillary electrophoresis/electrochromatography with sol-gel modified inner capillary wall

- Sol-gel stationary phase for open- tubular capillary electrochromatography was developed.
- Sol-gel containing porphyrin-brucine conjugate system was tested.
- Analysis of oligopeptides, nucleotides etc. at various conditions was demonstrated.

The aim of this article is to study the modification of an inner capillary wall with sol-gel coating (pure silica sol-gel or silica sol-gel containing porphyrin-brucine conjugate) and determine its influence on the separation process using capillary electrophoresis/electrochromatography method. After modification of the inner capillary surface the separation of analytes was performed using two different phosphate buffers (pH 2.5 and 9.0) and finally the changes in electrophoretic mobilities of various samples were calculated. To confirm that the modification of the inner capillary surface was successful, the parts of the inner surfaces of capillaries were observed using scanning electron microscopy. The analytes used as testing samples were oligopeptides, nucleosides, nucleobases and finally nucleotides.