Analysis of difference of serum proteins between patients with cirrhosis and normal people by capillary electrophoresis with light-emitting diode induced fluorescence detection

Abstract

An experimental method of protein separation by capillary electrophoresis coupled with light-emitting diode induced fluorescence detection (CE-LED-IF) was established. The fluorescein isothiocyanate (FITC) was used as fluorescent dye in this method. An optical fiber was inserted into the separation capillary and was suited right at the detection window which was used to transmit the excitation light of LED. The efficiency of the light of LED and the detection limits of FITC was improved. The difference of serum proteins between the patients with cirrhosis and normal people was detected by this method. A series of effects on CE were studied, such as the wavelength of the light source and filter, the concentration and pH of the running buffer and the separation voltage. Then the optimized method was established for the determination of the serum proteins. The repeatability of CE-LED-IF was tested and the RSDs of migration time and peak area were 1. 14% and 3. 23% , respectively. The results showed that there were two specific peaks in cirrhosis serum. The differences between the patients with cirrhosis and normal people having statistical significance indicated that these proteins might be the potential biomarkers for cirrhosis diagnosis. The developed CE-LED-IF method proved suitable for the separation of serum proteins with good repeatability and supportable for the clinical diagnosis of cirrhosis.