Patent ID: 6074870
Filing Date: 2000-06-13
Classification: C12M,G01N

Abstract:
An apparatus for detecting microorganism growth comprising:a container comprising a culture medium, a blood specimen, and a head space having a concentration of a gas;a chemically sensitive composite material in said container for detecting microorganism growth within said container when illuminated with an intensity-modulated light, said chemically sensitive composite material being comprised of a first fluorescent material and a second fluorescent material;said first fluorescent material exhibiting a fluorescence decay time that depends on a first chemical parameter of said gas;said second fluorescent material exhibiting a fluorescence intensity that depends on a second chemical parameter of said gas and having a fluorescence decay time at least one order of magnitude shorter than the fluorescence decay time of said first fluorescent material;means for generating said intensity-modulated light using a single excitation source;means for detecting and analyzing a fluorescence emitted from said chemically sensitive composite material, wherein said means for detecting and analyzing include a single emission filter and a single photodetector and said first and second fluorescent materials have the same absorption spectrum and emission spectrum; andmeans for determining whether microorganism growth is occurring in said container based on changes in the analyzed fluorescence in response to changes in the first and second chemical parameters.