Redox enzymes have been assembled in a monolayer on a solid surface by a potential-assisted self-assembly method as well as a thiol-gold self-assembly method. These enzymes communicate electronically with the solid substrate through a molecular interface conducting polymer and a covalently bound mediator. An ordered antibody array has also been assembled on the solid surface by a combination of the Langmuir-Blodgett (LB) film method and the self-assembly method. An ordered monolayer of protein A is deposited on the solid surface by the LB method, which is followed by self assembly of antibody. Individual antigen molecules that are complexed with the antibody array have been quantitated selectively by atomic force microscopy (AFM), A TOL plasmid, encoding a xyl R binding protein for xyline and a firefly luciferase marker enzyme, has been implemented in a bacterial cell. The whole cell responds to environmentally hazardous substances such as xylene by emitting light.
