Microbial monitoring device

A method for determining the effects of an antibiotic or antimicrobial composition on a respiring microorganism comprising:

• (i) preparing a broth of said microorganism:
• (ii) contacting said broth with a sensor composition which comprises a fluorescent compound that exhibits a reduction in fluorescent intensity, when irradiated with light containing wavelengths which cause said compound to fluoresce, upon exposure to oxygen, wherein the presence of the sensor composition is non-destructive to the microorganism;
• (iii) admixing with said broth, a quantity of said antibiotic or antimicrobial composition;
• (iv) irradiating said sensor composition with light containing wavelengths which cause said fluorescent compound to fluoresce;
• (v) measuring or visually observing the fluorescent light intensity from said fluorescent compound while irradiating said sensor compound with said light;
• and
• (vi) comparing said measurement to that of a control wherein said control is selected from the group consisting of:
• a reagent control not in contact with a respiring microorganism or the antibiotic or antimicrobial composition, a reagent control in contact with a respiring microorganism but not in contact with the antibiotic or antimicrobial composition and a calculated threshold, wherein a change in fluorescent intensity relative to the control is indicative of the susceptibility or resistivity of the microorganisms to the quantity of said antibiotic or antimicrobial composition;
• and
• (vii) in the event that no such change is measured or observed, repeat steps (iv), (v) and (vi), as needed, to determine the effects of the antibiotic or antimicrobial on the respiring microorganisms.

(amended) A method for detecting the presence of respiring microorganisms in a fluid comprising:

• (i) contacting said fluid with a fluorescent sensor composition which comprises a fluorescent compound selected from the group consisting of tris-4,7-diphenyl-1,10-phenanthroline-ruthenium (II) chloride and tris-2,2'-bipyridyl ruthenium (II) chloride hexahydrate, wherein the presence of the sensor composition is non-destructive to the microorganism;
• (ii) irradiating said sensor composition with light containing wavelengths which cause said fluorescent compound to fluoresce;
• (iii) measuring or visually observing the fluorescent light intensity from said fluorescent compound while irradiating said sensor compound with said light;
• (iv) comparing said measurement to that of a control, wherein said control is selected from the group consisting of:
• a reagent control not in contact with respiring microorganisms and a calculated threshold, wherein a change in fluorescent intensity relative to the fluorescent intensity of the control is indicative of the presence of respiring microorganisms;
• and
• (v) in the event that no such increase is measured or observed, repeat steps (ii), (iii), and (iv), as needed, to detect the presence of respiring microorganisms in said fluid.

A method of determining the effect of an antibiotic or antimicrobial composition on a respiring microorganism comprising:

• (i) preparing a broth of said microorganism:
• (ii) contacting said broth with a sensor composition which comprises a fluorescent compound selected from the group consisting of tris-4,7-diphenyl-1,10-phenanthroline-ruthenium (II) chloride and tris-2,2'-bipyridyl ruthenium (II) chloride hexahydrate, wherein the presence of the sensor composition is non-destructive to the microorganism;
• (iii) admixing with said broth a quantity of said antibiotic or antimicrobial composition:
• (iv) irradiating said sensor composition with light containing wavelengths which cause said fluorescent compound to fluoresce;
• (iv) measuring or visually observing the fluorescent light intensity from said fluorescent compound while irradiating said sensor compound with said light;
• (v) comparing said measurement to that of a control, wherein said control is selected from the group consisting of:
• a reagent control not in contact with a respiring microorganism or the antibiotic or antimicrobial composition, a reagent control in contact with a respiring microorganism but not in contact with the antibiotic or antimicrobial composition and a calculated threshold, wherein a change in fluorescent intensity relative to the control is indicative of the susceptibility or resistivity of the microorganisms to quantity of the antibiotic or antimicrobial composition:
• and
• (vi) in the event that no such change is measured or observed, repeat steps (iii), (iv), and (v), as needed, to detect the presence of respiring microorganisms in said fluid.