Temperature and denaturing substances influence on Lab-on-a-chip electrophoresis

Abstract

Qualitative and quantitative determination of proteins in different biological fluids is of great significance in medicine, due to their importance in diagnosis and treatment of some diseases. Nowadays, different methods for protein analysis are available. Lab-on-a-chip electrophoresis is a relatively new technique, based on micro fluidics, which allows samples of biological fluids to be analyzed within a microchip. This paper describes the optimization of performance of the chip-based protein analyses in serum samples from patients with different neurological disorders. Using microchip technology, serum proteins with the molecular mass from 4.5 to 240 Kb were separated and sized. The fluorescence detection method in the analysis was used to follow the influence of the temperature and the type and concentration of denaturing substances on the electrophoresis protein profiles. It was noted that, de pending on incubation temperature and denaturing substances, different electrophoresis patterns can be obtained from the proteins of one specimen. Significant change of the fluorescence intensity was observed when different incubation temperatures were used, probably due to fluorescence quenching. In some cases, the band intensity was changed several times. Lab-on-a-chip electrophoresis is a very efficient method for the separation and determi nation of different serum proteins in a very short time. However, to obtain comparable results for the analysis, the denaturing agent concentration and temperature must be observed and maintained carefully.

Keywords

• electrophoresis
• fluorescence quenching
• lab-ona-chip
• neurological diseases
• protein analysis
• serum samples