Electrostatic Force Microscopy of Biofilms and Arrayed Proteins for Biochip Applications
Y.J. Oh, W. Jo
Ewha Womans University, KR
EFM, biofilm, protein array
Scanning probe microscopy (SPM) is known to be a very useful tool for observation of biological samples, from single molecules to cells. A variety of SPM provides the quantitative information about interaction forces between tip and sample surface in addition to topographic information as the tip scans across the sample surface. We report growth media dependence of electrostatic force characteristic of Escherichia coli O157:H7 biofilm through local measurement by electrostatic force microscopy (EFM). Bacterial surface charge is an important factor for bacterial adhesion and using EFM, local electrical property of the cell surface can be addressed directly while conventional zeta-potential measurement is a sum of large area signals. This study undertaken to characterize the surface properties of E. coli O157:H7 and the influence of different media on their ability to adhere and grow on abiotic surface. Also the difference of cell surface charge in different media was investigated. Also, we describe a straightforward approach to the 2-dimensional immobilization of various proteins by micro-contact printing method. The lattice deposited by CP which is 4-6 nm height is an effective chemical barrier for bacteria behavior. With AFM, it is convenient to measure topography from the patterned surface allowing us to monitor the nano-scale barrier. And then we investigated the adhesion of bacteria onto substrates patterned with bovine serum albumin.
Nanotech 2008 Conference Program Abstract