Development of simple and reliable protocols for the immobilization of enzymes is an important aspect of nano biotechnology. Silver nanoparticles are known to bind enzymes, but reuse characteristics of the silver nano-enzyme bioconjugates has hithero been poor. In this paper, we demonstrate that silver nanoparticles bound at high surface coverage on polyurethane.  This material can be washed, dried, and stored for extended periods without the loss of nanoparticles. The performance of the material is as an antibacterial filter   The silver nanoparticle coated on polyurethane then act as templates for the immobilization of the enzyme butyrylcholinesterase (BuChE). BuChE in the bioconjugate system shows enhanced stability toward harsh temperature and pH conditions.