Using Temperature to Optimize Capillary Electrophoresis Separations

LEONARDO G. GAGLIARDI; JETSE C. REIJENGA; ERNST KENNDLER

Ciudad Autonoma de Buenos Aires

Simposio; 18th Latin-American Symposium on Biotechnology, Biomedical, Biopharmaceutical and Industrial Applications of Capillary Electrophoresis and Microchip Technology (LACE 2012); 2012

LACE Scientiffic Comitee

P { margin-bottom: 0.21cm; direction: ltr; color: rgb(0, 0, 0); }P.western { font-family: "Liberation Serif","Times New Roman",serif; font-size: 12pt; }P.cjk { font-family: "WenQuanYi Micro Hei","MS Mincho"; font-size: 12pt; }P.ctl { font-family: "Lohit Hindi"; font-size: 12pt; }A.western:link { }A.ctl:link { } Since temperature is an easy-to-control parameter, it is interesting to use it to improve CE separations. There is a general assumption that the temperature can change the viscosities and mobilities of the fully ionized ions, reducing the time of analysis. However, in addition to this effect, the temperature affects many other conditions1. For the aim of optimizing CE separations we can use temperature to selectively change the ionization degree of analytes2,3. On our first approach we have shown how to select the buffer compounds linking the temperature with the ionization degree of analytes2. Under this condition, any change of temperature during the electrophoretic run influences both mobilities and selectivities of analytes. In this work we propose the use of equations that give the temperature dependences of mobilities, pKa and buffer pH, to obtain a model predicting the selectivities as a function of temperature. This model, fed by just a few experimentally determined parameters, can provide the temperature or even temperature program, necessary to achieve the optimum separation of analytes. Different examples for each case will be shown and explained.