Abstract: There is disclosed an improved method for testing for the presence of a particular microorganism or group of microorganisms characterized by a particular enzyme. The method uses a dye-forming substrate throughout a polymer matrix or on the surface of a solid support member that forms a colored precipitate when cleaved by the enzyme. The precipitate is concentrated to the polymer matrix and/or solid support member to create a visible reaction product, wherein the amount of dye-forming substrate needed is independent of the sample size. The present invention further comprises an enzyme indicator device comprising a dye-forming substrate throughout a polymer system or on the surface of a solid support member.

Abstract: A device is adapted for containing a volume of growth medium and employed for detection of gas produced by a microorganism or microorganisms putatively contained within a test sample and added to the growth medium, comprising a primary chamber, a dome defined by the top surface of the primary chamber and communicating therewith, the dome establishing a fluid level and adapted for collection of gas produced by a microorganism within the growth medium, and a fill section adjacent to and communicating with one end of the primary chamber, the fill section spaced apart from the dome and extending above the fluid level, and further defining an opening for the addition of a test sample. The device may be sealed by means of a removable closure. An apparatus also consists of an array of substantially identical devices is also disclosed.