Sensor for detecting microorganisms

• US 5,809,185 A
• Filed: 04/26/1996
• Issued: 09/15/1998
• Est. Priority Date: 04/26/1996
• Status: Expired due to Term

• Current Assignee: Echo Technologies Incorporated
• Original Assignee: Altran Cis (Altran Technologies), TDSM Limited Liability Company
• Inventors: Mitchell, Ralph
• Primary Examiner(s): NGO, HUNG NHAT
• Application Number:
  US08/638,278
• Time in Patent Office: 872 Days
• Field of Search: 385/12, 385/128, 250/227.11, 250/227.14, 250/227.18
• US Class Current: 385/12
• CPC Class Codes: G01N 21/648 using evanescent coupling or surface plasmon coupling for the excitation of fluorescence
• CPC Class Codes: G01N 21/7703 using reagent-clad optical fibres or optical waveguides using measurement of total internal reflection or attenuated total reflection G01N21/552; optical fibres or waveguides per se G02B
• CPC Class Codes: G02B 6/02 Optical fibres with cladding with or without a coating

Abstract

A sensor for detecting microorganisms in air, water, or deposited on surfaces. The sensor includes a source of light, a waveguide receptive to the source of light, a fluorochrome coating on the waveguide, and a detector which detects the Stokes shift of light passing through the waveguide in response to microorganisms fluorescing as they come into contact with the fluorochrome coating on the waveguide.

Claims

1. A sensor for detecting microorganisms, the sensor comprising:

a source of light;

a waveguide receptive to said source of light;

a fluorochrome coating on the waveguide; and

means for detecting the Stokes shift of the light passing through the waveguide in response to microorganisms fluorescing as they come into contact with the fluorochrome coating.

2. The sensor of claim 1 in which said waveguide is a porous optical fiber.

3. The sensor of claim 1 in which said source of light is broadband.

4. The sensor of claim 3 in which said broadband source of light includes a tungsten lamp.

5. The sensor of claim 1 in which said source of light includes a source of coherent light.

6. The sensor of claim 1 in which said means for detecting includes a photodetector tuned to detect said Stokes shift.

7. The sensor of claim 1 further including an indicator, responsive to said means for detecting, for providing an indication of the presence of a detected microorganism.

8. The sensor of claim 1 further including a first filter disposed between the source of light and the waveguide and a second filter disposed between the waveguide and the means for detecting.

9. The sensor of claim 8 in which the first filter passes light in wavelengths corresponding to the absorbance of the fluorochrome coating and the second filter passes light in wavelengths corresponding to the emissivity of the fluorochrome coating.

10. A sensor for detecting microorganisms, the sensor comprising:

at least one source of light;

a plurality of waveguides receptive to said source of light;

a different fluorochrome coating on each said waveguide; and

means for separately detecting the Stokes shift of the light traveling through the waveguides in response to different microorganisms fluorescing as they come into contact with the different fluorochrome coatings on the waveguides.

11. A sensor for detecting microorganisms, the sensor comprising:

a source of light;

a waveguide receptive to said source of light;

a first filter disposed between the source of light and the waveguide;

a fluorochrome coating on the waveguide;

means for detecting the Stokes shift of the light passing through the waveguide in response to microorganisms fluorescing as they come into contact with the fluorochrome coating; and

a second filter disposed between the waveguide and the means for detecting.

12. The sensor of claim 11 in which the first filter passes light in wavelengths corresponding to the absorbance of the fluorochrome coating and the second filter passes light in wavelengths corresponding to the emissivity of the fluorochrome coating.