AVS 50th International Symposium
    Biomaterial Interfaces Thursday Sessions
       Session BI+SS-ThA

Paper BI+SS-ThA8
Adsorption Behavior of Proteins in Microcapillaries

Thursday, November 6, 2003, 4:20 pm, Room 318/319

Session: Biodiagnostics
Presenter: A. Bhattacharyya, Clemson University
Authors: A. Bhattacharyya, Clemson University
K. Lenghaus, Clemson University
D. Halagowder, Clemson University
J.J. Hickman, Clemson University
J.W. Jenkins, CFD Research Corporation
S. Sundaram, CFD Research Corporation
Correspondent: Click to Email
The dynamics of protein adsorption, desorption and denaturization are important factors in determining the efficacy of a microfluidic device for biotechnology applications. When a protein solution is passed through a microcapillary, the protein molecules can adsorb onto the surface of the capillaries and can often subsequently denature. Hence an understanding of the adsorption behavior of a protein is very important in order to determine the basic parameters for fabrication of a microfluidic based MEMS device. Most of the research on protein adsorption characteristics is based on static systems. However, the adsorption behavior of proteins in static and flow systems is not necessarily the same. Our research focuses on investigating the difference in the adsorption behavior of proteins under flow and static conditions, using enzymatic proteins as probes. We have used enzymes such as alkaline phosphatase, glucose oxidase and horseradish peroxidase in our studies. The microcapillaries used were PEEK (Poly-Ether-Ether-Ketone) and PTFE (Polytetrafluoroethylene). A total protein assay (MicroBCA) was used to quantitate the amount of protein adsorbed to the surface and enzymatic assays were used to estimate the activity of the proteins. A statistical model based on the Langmuir equation was used for extracting the kinetic binding constants and the protein coverage on the surface. Our results indicate that there is a significant difference in the surface affinities and binding site densities observed in static and flow conditions. These results will enable us to improve existing protein adsorption and fluid dynamics software and eventually create design rules for biocompatible MEMS devices.