Patent ID: 7939291

Claim:
A method of determining the presence of a microbial infection or contamination in a sample, the method comprising the sequential steps of: (a) contacting a sample with an amebocyte lysate comprising an activatable enzyme to produce a sample-lysate mixture, whereupon the enzyme becomes activated if a microbial contaminant that activates the enzyme is present in the sample; (b) after step (a), contacting the sample-lysate mixture with a substrate for the enzyme to produce a sample-lysate-substrate mixture, such that, if the mixture contains activated enzyme, the activated enzyme produces a change in the substrate; (c) determining the time in which a preselected change occurs in an optical property of the sample-lysate-substrate mixture, wherein the change in optical property results from a change in the substrate; and (d) comparing the time determined in step (c) against a predetermined standard curve to determine whether the microbial infection or contamination is present in the sample.