Handheld fluorometer

Patent metadata

Field	Value
Publication number	US-2016047746-A1
Application number	US-201414457573-A
Country	US
Kind code	A1
Filing date	Aug 12, 2014
Priority date	Aug 12, 2014
Publication date	Feb 18, 2016
Grant date	—

Abstract

A fluorometer for measuring fluorescence of a sample includes an excitation source for emitting electromagnetic radiation along a first beam path to induce fluorescence in the sample. An excitation filter transmits electromagnetic radiation from the excitation source toward the sample. An excitation filter holder supports the excitation filter and defines an aperture for passage of electromagnetic radiation from the excitation source. The aperture is positioned asymmetrically relative to the first beam path such that the aperture allows an asymmetrical portion of the electromagnetic radiation in the first beam path to pass toward the sample and the excitation filter holder blocks passage of a corresponding asymmetrical portion of the electromagnetic radiation in the first beam path. The blocked passage of the corresponding asymmetrical portion of the electromagnetic radiation in the first beam path reduces the amount of electromagnetic radiation oriented directly from the emitter module to the detector module.

First claim

What is claimed is:

1 . A fluorometer for measuring fluorescence of a sample comprising dipicolinic acid, the fluorometer comprising:
a housing; a controller supported by the housing, the controller configured for determining a concentration of a substance in the sample based on a detected fluorescent emission; and a sensor head comprising:
an emitter module operatively coupled to the controller and including:
an excitation source configured for emitting electromagnetic radiation at one or more wavelengths to induce fluorescence in the sample, the emission of the electromagnetic radiation being directed along a first beam path,
an excitation filter configured for transmitting electromagnetic radiation within a first wavelength range toward the sample, and
an excitation filter holder supported by the housing and defining an aperture for passage of electromagnetic radiation, the excitation filter holder adapted to support the excitation filter such that the excitation filter filters electromagnetic radiation emitted by the excitation source to within the first wavelength range and permits passage of such filtered electromagnetic radiation through the aperture and towards the sample such that the first beam path defines a trajectory of electromagnetic radiation from the excitation source to the excitation filter, via the aperture and toward the sample, and
a detector module operatively coupled to the controller, the detector module configured for detecting fluorescence emitted by the sample, wherein the fluorometer displays the concentration of the substance in the sample determined by the controller,
the aperture being positioned asymmetrically relative to the first beam path such that the aperture passes an asymmetrical portion of the electromagnetic radiation in the first beam path and the excitation filter holder blocks passage of a corresponding asymmetrical portion of the electromagnetic radiation in the first beam path, the blocked passage of the corresponding asymmetrical portion of the electromagnetic radiation in the first beam path reducing the amount of electromagnetic radiation oriented directly from the emitter module to the detector module.

2 . The fluorometer of claim 1 , further comprising a first focusing apparatus and a second focusing apparatus, the first focusing apparatus and the second focusing apparatus housed in the housing, the first focusing apparatus adapted to direct electromagnetic radiation originating from the excitation source and transmitted by the excitation filter towards the sample, and the second focusing apparatus adapted to direct fluorescence originating from the sample toward the detector module.

3 . The fluorometer of claim 2 , wherein the aperture is of semi-circular cross-section.

4 . The fluorometer of claim 2 , wherein the aperture is shaped to prevent electromagnetic radiation passing through the first focusing apparatus from being directed toward the second focusing apparatus.

5 . The fluorometer of claim 1 , wherein the aperture is shaped by obstructing at least a portion of a circular opening.

6 . The fluorometer of claim 1 , further comprising a reference photodetector supported by the emitter module, the reference photodetector configured for measuring a reference signal representative of electromagnetic radiation emitted by the excitation source.

7 . The fluorometer of claim 6 , further comprising an attenuator obstructing a least a portion of the reference photodetector, the attenuator configured for providing spatially uniform attenuation of electromagnetic radiation emitted by the excitation source over a surface area of the attenuator such that the attenuator helps prevent the reference photodetector from being saturated with electromagnetic radiation.

8 . The fluorometer of claim 7 , wherein the attenuator comprises a layer of polytetrafluoroethylene bonded to the emitter module.

9 . The fluorometer of claim 1 , further comprising an emission filter housed on the detector module, the emission filter configured for transmitting fluorescence emitted by the sample to the detector module.

10 . The fluorometer of claim 9 , wherein the emission filter is configured for transmitting electromagnetic radiation within a second wavelength range toward a photodetector housed on the detector module.

11 . The fluorometer of claim 10 , wherein the first wavelength range is about 250 nanometers to 300 nanometers.

12 . The fluorometer of claim 11 , wherein the second wavelength range is about 400 nanometers to 700 nanometers.

13 . The fluorometer of claim 10 , wherein the photodetector comprises a photodiode.

14 . The fluorometer of claim 9 , wherein the emission filter comprises polycarbonate having a thickness of between about 2 millimeters and about 4 millimeters.

15 . The fluorometer of claim 9 , wherein the emission filter comprises a narrow band interference filter having a bandwidth between about 2 nanometers and about 10 nanometers.

16 . The fluorometer of claim 1 , wherein the excitation source emits electromagnetic radiation at 275 nanometers to induce fluorescence in the sample.

17 . The fluorometer of claim 1 , wherein the sensor head is disposed about a sensor head axis, the sensor head axis forming an angle of about 20 degrees to about 90 degrees with an axis of the housing.

18 . The fluorometer of claim 1 , wherein the excitation source comprises a light-emitting diode.

19 . A method of measuring concentration of a substance in a sample comprising dipicolinic acid in a solution with a fluorometer, comprising:
providing a fluorometer, comprising:
a housing,
a controller supported by the housing, and
a sensor head coupled to the housing, comprising:
an emitter module operatively coupled to the controller and including:
an excitation source,
an excitation filter, and

a detector module operatively coupled to the controller,

emitting electromagnetic radiation at one or more wavelengths; transmitting the emitted electromagnetic radiation at a first wavelength range toward the sample; directing the electromagnetic radiation toward the sample along a first beam path, such that the first beam path defines a trajectory of electromagnetic radiation from the excitation source to the excitation filter toward the sample; permitting an asymmetrical portion of the electromagnetic radiation toward the sample and blocking a corresponding asymmetrical portion of the electromagnetic radiation, the blocked corresponding portion of electromagnetic radiation reducing the amount of electromagnetic radiation oriented directly from the emitter module to the detector module; and measuring the emitted fluorescence, thereby determining the concentration of the substance in the sample.

Assignees

• Ecolab Usa Inc

Inventors

• Tokhtuev Eugene
• Skirda Anatoly
• Pilipchenko Anna
• Bolduc John Wilhelm
• Valenstein Justin Scott

Classifications

• G01N21/6428

  Measuring fluorescence of fluorescent products of reactions or of fluorochrome labelled reactive substances, e.g. measuring quenching effects, using measuring "optrodes" (in vivo A61B5/00; immunoassay G01N33/53) · CPC title

• G01N21/6486

  Measuring fluorescence of biological material, e.g. DNA, RNA, cells (G01N21/6428 takes precedence) · CPC title

• G01N2201/068

  Optics, miscellaneous · CPC title

• G01N21/8507

  Probe photometers, i.e. with optical measuring part dipped into fluid sample · CPC title

• G01N21/645 Primary

  Specially adapted constructive features of fluorimeters · CPC title