Study on Phosphate of Ethylenediamine, 1,3-Diaminopropane and 1,4-Diaminobutane as Carrying Electrolyte in Open-Tubular Capillary Electrophoresis

Abstract The use of ethylenediamine, 1,3-diaminopropane and 1,4 -diminobutane phosphate as carrying electrolyte in open- tubular capillary electrophoresis is proposed. The advantage of them as carrying electrolyte was found in the ability to slow electroosmotic mobility because of adsorption of their ions to the capillary inner wall which caused decrease of ζ potential of the wall. Difference among ethyienediamine, 1,3-diminopropane and 1,4-diaminobutane lies in their adsorption, and enthylene diamine gave higher electroosmotic mobility than other two at same concentration maybe due to its weak adsorption. The dependence of electroosmotic mobility on diamine concentration, pH, neutral salt concentration and applied voltage was determined. Increased diamine concentration caused decrease of electroosmotic mobility, but increased pH, neutral salt concentration and applied voltage gave reversed effects. The addition of neutral salt caused decreased adsorption of diamine ions, and the increased applied voltage...