Patent ID: 8084247

Claim:
A biological indicator for monitoring sterility, comprising: a substrate; a plurality of functional groups residing on an exposed surface of said substrate, said functional groups containing about 10% or less of any silicon linking atoms, based upon the total amount of said functional groups; a plurality of microorganism indicators comprising an endospore, a fungi, a mycobacteria, a vegetative bacteria, a protozoa, or any combination thereof; a photoreactive crosslinking agent having one functional end group covalently bonded to one of said surface functional groups and having another functional end group covalently bonded to one of said microorganism indicators, so that a terminal and exposed microorganism indicator is present that is covalently bonded through said crosslinking agent to said substrate, said substrate having a plurality of said terminal and exposed microorganisms bound thereto that are capable of being sterilized by a sterilizing medium, wherein said plurality of said exposed and bound microorganisms covalently bonded through said crosslinking agent to the surface of said substrate have a uniform distribution, wherein the standard deviation of the distribution is about 50% or less based on one unit area of said surface as compared to another unit area of said surface, and wherein the photoreactive crosslinking agent comprises N-Succinimidyl-6-[4′-azido-2′-nitrophenylamino]hexanoate (SANPAH).