Development of capillary electrophoresis equipment for salt removing from protein solutions

Abstract

Protein precipitation by salts is often used method for protein purification. One of must often used salt for protein precipitation is ammonium sulfate. After protein precipitation procedure, protein solution requires method to remove salts from solution. The aim of this study was to develop on capillary electrophoresis principles based equipment to remove salts from protein solution. Cheap and easy to access parts were chosen to construct apparatus. Lysozyme solution after purification by protein precipitation procedure was used as sample to test effectiveness of apparatus. Salt removing conditions were: 0,5 M, pH=2.58 acetic acid was used as background electrolyte; capillary length – 12 centimeters; applied voltage – 2,7 kV; sample volume up to 1 ml. After salt removing procedure, sample were analyzed using capillary zone electrophoresis. Analysis conditions were; 0,5 M acetic acid was used as background electrolyte, applied voltage was 14 kV. Injection 50mbar*30s; analysis time 40 minutes. Detector type – contactless conductivity detector.