EP1076815A1 - Module entierement base sur fibres optiques destine a un systeme optique de detection chimique - Google Patents

Module entierement base sur fibres optiques destine a un systeme optique de detection chimique

Info

Publication number
EP1076815A1
EP1076815A1 EP00913762A EP00913762A EP1076815A1 EP 1076815 A1 EP1076815 A1 EP 1076815A1 EP 00913762 A EP00913762 A EP 00913762A EP 00913762 A EP00913762 A EP 00913762A EP 1076815 A1 EP1076815 A1 EP 1076815A1
Authority
EP
European Patent Office
Prior art keywords
optical
proximal
optical fiber
distal
end portion
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Withdrawn
Application number
EP00913762A
Other languages
German (de)
English (en)
Inventor
Jamie N. Lussier
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Yellow Springs Optical Sensor Co PLL
Original Assignee
Yellow Springs Optical Sensor Co PLL
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Yellow Springs Optical Sensor Co PLL filed Critical Yellow Springs Optical Sensor Co PLL
Publication of EP1076815A1 publication Critical patent/EP1076815A1/fr
Withdrawn legal-status Critical Current

Links

Classifications

    • GPHYSICS
    • G01MEASURING; TESTING
    • G01NINVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
    • G01N21/00Investigating or analysing materials by the use of optical means, i.e. using sub-millimetre waves, infrared, visible or ultraviolet light
    • G01N21/75Systems in which material is subjected to a chemical reaction, the progress or the result of the reaction being investigated
    • G01N21/77Systems in which material is subjected to a chemical reaction, the progress or the result of the reaction being investigated by observing the effect on a chemical indicator
    • G01N21/7703Systems in which material is subjected to a chemical reaction, the progress or the result of the reaction being investigated by observing the effect on a chemical indicator using reagent-clad optical fibres or optical waveguides
    • GPHYSICS
    • G01MEASURING; TESTING
    • G01NINVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
    • G01N21/00Investigating or analysing materials by the use of optical means, i.e. using sub-millimetre waves, infrared, visible or ultraviolet light
    • G01N21/75Systems in which material is subjected to a chemical reaction, the progress or the result of the reaction being investigated
    • G01N21/77Systems in which material is subjected to a chemical reaction, the progress or the result of the reaction being investigated by observing the effect on a chemical indicator
    • G01N21/7703Systems in which material is subjected to a chemical reaction, the progress or the result of the reaction being investigated by observing the effect on a chemical indicator using reagent-clad optical fibres or optical waveguides
    • G01N2021/7706Reagent provision
    • G01N2021/7733Reservoir, liquid reagent
    • GPHYSICS
    • G01MEASURING; TESTING
    • G01NINVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
    • G01N21/00Investigating or analysing materials by the use of optical means, i.e. using sub-millimetre waves, infrared, visible or ultraviolet light
    • G01N21/75Systems in which material is subjected to a chemical reaction, the progress or the result of the reaction being investigated
    • G01N21/77Systems in which material is subjected to a chemical reaction, the progress or the result of the reaction being investigated by observing the effect on a chemical indicator
    • G01N2021/7769Measurement method of reaction-produced change in sensor
    • G01N2021/7786Fluorescence

Definitions

  • the present application is directed to an optical chemical sensing system and. more particularly, to a sensor system using the optical absorption or fluorescence of a fluid dye material to measure the concentration of a dissolved analyte.
  • analyte measuring instruments have been designed and developed for use in numerous medical, industrial and environmental applications.
  • these devices are those that rely on optical properties of a sensing element containing a dye material which is responsive to a particular analyte.
  • optical characteristics of the dye material such as the absorption or fluorescence spectrum, change to a degree related to the concentration of the analyte in the surrounding medium.
  • certain prior art devices trap an aqueous dye solution in a sensor element or probe between an exposed analyte-permeable membrane and a distal end of at least one optical fiber.
  • analyte molecules diffuse through the membrane and interact with the dye solution.
  • Light at one or more selected frequencies illuminates the dye solution.
  • the optical fiber gathers reflected or fluoresced light from the dye solution and conducts the reflected or fluoresced light to one or more transducers.
  • the one or more transducers provide a measure of the intensity of the reflected or fluoresced light corresponding to the one or more selected illumination frequencies which correlate, in turn, with the concentration of the analyte in the medium.
  • pH sensors using mildly acidic dyes which are capable of dissociating to form conjugate bases having absorption and fluorescence spectra different from the corresponding spectra of the dyes themselves.
  • dissolved carbon dioxide sensors by associating an aqueous sodium bicarbonate solution with such an acidic dye material, separated by a hydrogen ion-permeable membrane. In the latter sensors, dissolved carbon dioxide interacts with the sodium bicarbonate solution to produce dissolved hydrogen ion. which suppresses the dissociation of the dye and alters the optical properties of the dye solution.
  • Dichroic mirrors comprise materials or coatings which reflect certain frequencies of light and transmit others. When one or more dichroic mirrors are arranged along a path, they can be used to direct light of different frequencies along different paths so that separate intensity measurements can be made at different frequencies.
  • Dichroic mirrors are expensive to prepare and contribute significantly to the cost of the sensor system. They tend to be bulky and require some care to avoid breakage. Beyond this, free standing optical elements such as dichroic mirrors must be carefully aligned so that the disparate elements communicate optically with each other. This alignment further increases the cost of such systems.
  • a preferred sensor system includes a sensor element or probe; a distal optical fiber communicating with the probe; and a plurality of proximal optical fibers having distal ends fused to a proximal end of the distal optical fiber so as to conduct light between the distal optical fiber and the plurality of proximal optical fibers.
  • Optical fibers are typically formed of amorphous, light transmissive materials such as fused silicon. Radial variations in the refractive indices channel light along the lengths of the fibers. Where portions of optical fibers formed of the same material are melted and fused together, such fused joints are homogenous in character and present little impedance to light propagating therethrough.
  • first, second and third proximal optical fibers are fused to a proximal end of a single distal optical fiber.
  • Proximal ends of the first and second proximal optical fibers each communicate with monochromatic light sources of different frequencies while a proximal end of the third proximal optical fiber communicates with a frequency-sensitive photodetector system.
  • the first and second proximal optical fibers each conduct light through the fused joint between the proximal and distal optical fibers toward the probe.
  • Output light from the probe (such as reflected or fluoresced light from a dye solution) returns through the distal optical fiber.
  • the output light enters the third proximal optical fiber through the fused joint and propagates toward the frequency-sensitive photodetector system.
  • the first proximal optical fiber communicates with a monochromatic light source while the second and third proximal optical fibers communicate with frequency-sensitive photodetector systems.
  • the monochromatic light propagates through the first proximal optical fiber, the fused joint and the distal optical fiber toward the probe.
  • Output light from the probe returns through the distal optical fiber; divides at the fused joint; and propagates through each of the second and third proximal optical fibers toward the frequency-sensitive photodetector systems.
  • proximal optical fibers While in each case the especially preferred embodiments have been described as having three proximal optical fibers, there is no limitation in theory on the number of proximal optical fibers which may be fused to the distal optical fiber. Instead, the number of such proximal fibers used is a matter of design choice depending on the application for which the sensor is to be used.
  • the fused joints referred to in the foregoing descriptions need not result from direct fusion of the proximal end of the distal optical fiber with the distal ends of the proximal optical fibers.
  • the proximal end of the distal optical fiber and the distal ends of the proximal optical fiber may each be fused to opposite ends of a mixing section of optical fiber rather than directly to each other.
  • a bleed optical fiber fused in parallel with the distal optical fiber communicates with a reference photodetector.
  • the bleed optical fiber has a diameter less than that of the distal optical fiber so that less light flows into the bleed fiber than into the distal fiber.
  • the reference photodetector provides a reference light level which can be used to compensate for variations in the intensities of light produced by the monochromatic light sources.
  • an all fiber optic module which eliminates the need for bulky, expensive optical elements such as dichroic mirrors in optical chemical sensor systems. This allows for the encapsulation of the all fiber optic module within a portable housing. Unlike a dichroic-based system, the all fiber optic modules described above may be encapsulated in a moisture-resistant electronic assembly potting compound for use in severe environments. The optical elements need not be carefully aligned because the optical fibers channel light from one element to the next. As a result, the cost of an optical chemical sensor system using the all fiber optic module will likely be less than that of systems using free-standing optical elements.
  • FIG. 1 is a schematic view of a first embodiment of an optical chemical sensor system including an all fiber optic module in accordance with the invention
  • Fig. 2 is a schematic disassembled view of a preferred sensor element or probe for use in the optical chemical sensor system of Fig. 1 :
  • Fig. 3 is a schematic view of a second embodiment of an optical chemical sensor system including an all fiber optic module in accordance with the invention.
  • a first preferred embodiment of an optical chemical sensor system 10 such as a system for measuring dissolved carbon dioxide.
  • a sensor element or probe 12 includes a sensor element or probe 12, a distal optical fiber 14, a first proximal optical fiber 16. a second proximal optical fiber 18. a third proximal optical fiber 20.
  • a first monochromatic light source 22 includes a second monochromatic light source 24.
  • a preferred probe 12 for use in a dissolved carbon dioxide sensor comprises a sensor capsule 40 housed between a sensor housing 42 and a sensor cap 44.
  • the sensor capsule 40 includes an outer housing 46; an insert member 48: a perforated metal disc 50: a C0 2 -permeable silicone membrane 52: and a light-transmissive polytetrafluoroethylene (“PTFE”) membrane
  • the outer housing 46 and the insert member 48 snap together around the perforated disc 50 and the membranes 52. 54 to form a unitary capsule 40 which may be easily removed and replaced without sacrificing the entire probe 12.
  • a pool 56 of a aqueous solution of a weakly acidic dye and carbonate ion is trapped in the preferred probe 12 between the silicone membrane 52 and the
  • a distal end 58 of the distal optical fiber 14 extends through the sensor housing 42 into optical communication with the aqueous dye solution 56 through the PTFE membrane 54.
  • the PTFE membrane 54 separates and protects the distal end 58 of the distal optical fiber 14 (Fig. 1) from aqueous dye solution 56.
  • the optical fibers 14. 16. 18, 20 are each preferably formed of an amorphous, light transmissive material such as fused silicon. formulated in radial layers so as to channel the flow of light along their respective lengths. Distal ends 60. 62 and 64 of the proximal optical fibers 16.
  • the monochromatic light sources 22. 24 each comprise a light source 80. such as a bulb or a light emitting diode, and a band-pass filter 82 to isolate a frequency at which the aqueous dye solution (not shown) is to be illuminated.
  • the light source and the band-pass filter are of conventional construction.
  • the monochromatic light sources 22. 24 communicate with proximal ends 84. 86 of the first and second proximal optical fibers 16. 18 to permit the first and second proximal optical fibers 16, 18 to transmit monochromatic light from the monochromatic light sources 22, 24 toward the distal optical fiber 14.
  • the frequency-sensitive photodetector system 26 includes a band-pass filter 90 in optical communication with a measuring photodetector 92.
  • the bandpass filter 90 and the measuring photodetector 92 are of conventional construction.
  • the band-pass filter 90 communicates optically with a proximal end 94 of the third proximal optical fiber 20.
  • the frequency-sensitive photodetector system 26 measures the intensity of a component of light returning through the third proximal optical fiber 20 within a narrow energy range surrounding a selected frequency.
  • the bleed optical fiber 28 is fused to the distal optical fiber 14 so that it directs a portion of the light propagating through the distal optical fiber 14 toward the reference photodetector 30. It preferably is formed of an amorphous, light transmissive material such as fused silicon and has a diameter much less than a diameter of the distal optical fiber 14 so that the portion of light directed through the bleed optical fiber 28 toward the reference photodetector 30 is much less than the portion directed through the distal optical fiber 14 toward the probe 12. This permits the reference photodetector 30 to monitor the intensity of light output by the two monochromatic light sources 22. 24 so as to provide a reference level to correct for the effects of variations in the intensity of light produced by the sources 22. 24 on the intensity measured by the frequency-sensitive photodetector system 26.
  • the monochromatic light sources 22. 24; the photodetector 26: and the reference photodetector 30 each communicate electronically with a controller, such as a microprocessor (not shown).
  • the controller modulates the light illuminating the aqueous dye solution (not shown) in the probe 12. It also processes intensity measurements reported by the photodetector 26 and the reference photodetector 30 to derive analyte concentration measurements.
  • one preferred aqueous dye solution (not shown) for use in the optical chemical sensor system 10 of Fig. 1 is 8-hydroxypyrene-1.3,6-trisulfonic acid (HPTS). buffered with carbonic acid.
  • HPTS is a weak acid which decomposes to form dissolved hydrogen ion and a conjugate base. Dissolved carbon dioxide interacts with water in the dye solution to increase the supply of carbonic acid, which suppresses the dissociation of the HPTS into its conjugate base.
  • HPTS achieves peak fluorescent emission when excited at a wavelength of approximately 405 nm while its conjugate base achieves peak fluorescent emission at a wavelength of approximately 460 nm. Both HPTS and its conjugate base have fluorescent emission frequencies of approximately 515 nm.
  • the probe 12 containing the buffered aqueous solution of HPTS is exposed to a medium (not shown) so as to allow carbon dioxide from the medium to diffuse into the HPTS solution; if the HPTS solution is sequentially illuminated with monochromatic light having components with wavelengths of approximately 405 nm and 460 nm; and if the intensity of the fluorescent emission from the HPTS solution at a wavelength of approximately 515 nm is measured for each wavelength of illuminating light, a correlation exists between the partial pressure of dissolved carbon dioxide in the medium and the measured intensities of the fluorescent emission.
  • the monochromatic light sources 22. 24 supply light at frequencies in the vicinity of 405 nm and 460 nm. respectively.
  • Light from the two monochromatic light sources 22. 24 propagates through the first and second proximal optical fibers 16, 18: through the fused coupling 68: and through the distal optical fiber 14 toward the probe 12.
  • a controller such as a microprocessor-based controller (shown schematically at 100). may be used to turn the monochromatic light sources 22. 24 ON and OFF to modulate the light illuminating the HPTS solution in the probe 12.
  • Fluorescent emission from the HPTS solution returns through the distal optical fiber 14. the fused coupling 68 and the third proximal optical fiber 20 toward the frequency-sensitive photodetector system 26.
  • the frequency-sensitive photodetector system 26 measures the intensity of the fluorescent emission within a range of frequencies in the vicinity of 515 nm.
  • the reference photodetector 30 provides a reference illumination level which may be used to normalize the intensities measured by the frequency-sensitive photodetector system 26.
  • optical chemical sensor system 10 includes a microprocessor-based controller 100.
  • the values at pH 3 and pH 12 may be tabulated, and the pCO : value may be calculated, within the system 10.
  • a second preferred embodiment of an optical chemical sensor system 110 such as a system for measuring dissolved carbon dioxide, includes a sensor element or probe 112. a distal optical fiber 1 14, a first proximal optical fiber 116. a second proximal optical fiber 1 18. a third proximal optical fiber 120, a monochromatic light source 122. a first frequency-sensitive photodetector system 124. a second frequency-sensitive photodetector system 126. a bleed optical fiber 128 and a reference photodetector 130.
  • the preferred probe 112 (including the sensor housing 142 and the sensor cap 144) is similar in structure to the preferred probe 12 of Fig. 1, although the system 110 of Fig.
  • the preferred optical fibers 114. 116. 118, 120. 128 are similar in structure to the optical fibers 14, 16, 18, 20, 28 of Fig. 1.
  • the preferred monochromatic light source 122; the preferred frequency-sensitive photodetector systems 124. 126; and the reference photodetector 130 of Fig. 3 are similar in structure to the monochromatic light sources 22. 24: the frequency-sensitive photodetector system 26: and the reference photodetector 30 of Fig. 1. respectively, although the corresponding components of the two systems are likely to be set to different frequencies corresponding to the peak excitation and emission frequencies of the dye solutions used.
  • Distal ends 160, 162 and 164 of the proximal optical fibers 116. 1 18, 120 are fused to a proximal end 166 of the distal optical fiber 114 and encapsulated to form a fused coupling 168 with minimal impedance to the frequencies at which the dye solution (not shown) is to be illuminated and at which intensity measurements are to be taken.
  • optical fibers 14, 16. 18. 20 and 1 14. 116. 118, 120 in the optical chemical sensor systems 10 and 110 is accomplished via a laser fusion process.
  • the fibers to be fused together such as proximal optical fibers 16. 18 and 20 as shown in Fig. 1 , are fixtured in a chuck (not shown), and then rotated in the path of a focused 125 watt Carbon Dioxide laser beam (wavelength of 9.4 to 10.4 micrometers) (not shown).
  • the energy of the C0 2 laser beam heats up the three optical fibers to a temperature at which fusion occurs.
  • a similar process is performed with the distal optical fiber 14 and bleed fiber 28.
  • the region of fusion no longer contains an outer cladding layer, but is of sufficiently short distance that the optical losses are minimized and at an acceptable level.
  • both fused fiber units are mounted in rotating chucks (not shown) and the fused fiber unit ends are brought together in the focused beam path of the laser.
  • a mixing section of optical fiber (not shown).
  • a section of optical fiber is butt-end fused to both fused fiber units, such that the mixing section is located in between the two fused fiber units.
  • aqueous dye solution for use in the optical chemical sensor system 10 is an aqueous solution of carboxy-seminapthofluorescein (c-SNAFL), buffered with carbonic acid.
  • c-SNAFL carboxy-seminapthofluorescein
  • the buffered c-SNAFL solution indicates the partial pressure of dissolved carbon dioxide in a manner analogous to the buffered HPTS solution described earlier.
  • Both c-SNAFL itself and its conjugate base achieve peak fluorescent emission when excited by light at a wavelength of approximately 480 nm.
  • c-SNAFL fluoresces at a wavelength of approximately 540 nm while its conjugate base fluoresces at a wavelength of approximately 630 nm.
  • the probe 112 containing the buffered aqueous solution of c-SNAFL is exposed to a medium (not shown) so as to allow carbon dioxide from the medium to diffuse into the c-SNAFL solution; if the c-SNAFL solution is illuminated with light at a wavelength of approximately 480 nm; and if the intensities of the fluorescent emissions from the c-SNAFL solution at wavelengths of 540 nm and 630 nm are measured, a correlation exists between the partial pressure of dissolved carbon dioxide in the medium and the measured intensities of the fluorescent emission.
  • the monochromatic light source 122 supplies light within a narrow range of frequencies in the vicinity of 480 nm.
  • Light from the monochromatic light source 122 propagates through the first proximal optical fiber 116 and the distal optical fiber 114 toward the probe 112.
  • Fluorescent emission from the c-SNAFL solution returns through the distal optical fiber 114; divides at the fused coupling 168; and propagates through the second and third proximal optical fibers 118. 120 toward the frequency-sensitive photodetector systems 124, 126.
  • the frequency-sensitive photodetector system 124 measures the intensity of the fluorescent emission within a range of frequencies in the vicinity of 540 nm while the frequency-sensitive photodetector system 126 measures the intensity of the fluorescent emission within a range of frequencies in the vicinity of 630 nm.
  • optical chemical sensor system 110 includes a microprocessor-based controller (shown schematically at 200), the values at low pH and pH 12 may be tabulated, and the pC0 2 value may be calculated, within the system 110.
  • All components of the systems 10, 1 10 except the probes 12, 112 and the distal optical fibers 14, 1 14 may be encapsulated in a portable, fluid-tight housing (not shown) to provide durable units for making field measurements.
  • Conventional output devices (not shown) may be provided for reading or recording measurements performed by the system 10, 110.
  • the all fiber optic module may be encapsulated in a common electronic assembly potting compound (not shown), to provide reliable and robust environmental protection for use in applications associated with severe environments.
  • An optical system using dichroics is very susceptible to damage due to humidity and moisture. This concern is eliminated in a potted assembly.
  • potting of a dichroic-based system is not practical nor economically feasible.
  • the optical chemical sensor systems 10. 110 provide all fiber optic modules which eliminate the need for expensive optical elements such as dichroic mirrors.
  • a size reduction in the overall optical system may be realized with the all-fiber optical module approach, that is not practically achievable with the traditional dichroic based design.
  • the optical elements need not be carefully aligned because the optical fibers channel the light from one element to the next.
  • the cost of optical chemical sensor systems using the all fiber optic module, such as the systems 10, 110 will likely be less than that of systems using free standing optical elements.

Landscapes

  • Physics & Mathematics (AREA)
  • Chemical & Material Sciences (AREA)
  • Biochemistry (AREA)
  • General Health & Medical Sciences (AREA)
  • Plasma & Fusion (AREA)
  • Health & Medical Sciences (AREA)
  • Life Sciences & Earth Sciences (AREA)
  • Analytical Chemistry (AREA)
  • Engineering & Computer Science (AREA)
  • Chemical Kinetics & Catalysis (AREA)
  • General Physics & Mathematics (AREA)
  • Immunology (AREA)
  • Pathology (AREA)
  • Investigating Or Analysing Materials By The Use Of Chemical Reactions (AREA)
  • Investigating Or Analysing Materials By Optical Means (AREA)
  • Investigating, Analyzing Materials By Fluorescence Or Luminescence (AREA)
  • Investigating Or Analyzing Non-Biological Materials By The Use Of Chemical Means (AREA)

Abstract

L'invention concerne un détecteur chimique optique comprenant un élément détecteur (12), une fibre optique distale (14) communiquant avec l'élément (12) et plusieurs fibres optiques proximales (16, 18, 20) possédant des extrémités distales liées à une extrémité proximale de la fibre optique distale (14).
EP00913762A 1999-03-05 2000-03-03 Module entierement base sur fibres optiques destine a un systeme optique de detection chimique Withdrawn EP1076815A1 (fr)

Applications Claiming Priority (3)

Application Number Priority Date Filing Date Title
US12291399P 1999-03-05 1999-03-05
US122913P 1999-03-05
PCT/US2000/005839 WO2000052452A1 (fr) 1999-03-05 2000-03-03 Module entierement base sur fibres optiques destine a un systeme optique de detection chimique

Publications (1)

Publication Number Publication Date
EP1076815A1 true EP1076815A1 (fr) 2001-02-21

Family

ID=22405592

Family Applications (1)

Application Number Title Priority Date Filing Date
EP00913762A Withdrawn EP1076815A1 (fr) 1999-03-05 2000-03-03 Module entierement base sur fibres optiques destine a un systeme optique de detection chimique

Country Status (4)

Country Link
EP (1) EP1076815A1 (fr)
JP (1) JP2002538460A (fr)
CA (1) CA2330769A1 (fr)
WO (1) WO2000052452A1 (fr)

Families Citing this family (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN114088670A (zh) * 2021-11-01 2022-02-25 上海烁谱科技有限公司 一种自参比比率荧光pH传感器

Family Cites Families (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4849172A (en) * 1986-04-18 1989-07-18 Minnesota Mining And Manufacturing Company Optical sensor
US5047627A (en) * 1990-05-18 1991-09-10 Abbott Laboratories Configuration fiber-optic blood gas sensor bundle and method of making
US5272090A (en) * 1992-03-31 1993-12-21 Moshe Gavish Sensor element for determining the amount of oxygen dissolved in a sample
US5387525A (en) * 1993-09-03 1995-02-07 Ciba Corning Diagnostics Corp. Method for activation of polyanionic fluorescent dyes in low dielectric media with quaternary onium compounds
US5567624A (en) * 1995-04-27 1996-10-22 Utah Medical Products, Inc. Carbazine dyes and derivatives for pH measurement

Non-Patent Citations (1)

* Cited by examiner, † Cited by third party
Title
See references of WO0052452A1 *

Also Published As

Publication number Publication date
JP2002538460A (ja) 2002-11-12
WO2000052452A1 (fr) 2000-09-08
CA2330769A1 (fr) 2000-09-08

Similar Documents

Publication Publication Date Title
US5176882A (en) Dual fiberoptic cell for multiple serum measurements
EP0850409B1 (fr) PROCEDE DE DETECTION PAR FLUORESCENCE, POUR LE pH ET LA pCO2, A DOUBLE EXCITATION ET EMISSION UNIQUE SIMULTANEES
US5039492A (en) Optical pH and gas concentration sensor
US5039491A (en) Optical oxygen sensor
Kostov et al. Low-cost optical instrumentation for biomedical measurements
AU614649B2 (en) Optical fiber distribution system for an optical fiber sensor
KR20070085230A (ko) 형광 рH 검출기 시스템 및 관련 방법
KR101224330B1 (ko) 에버네센트 카테터 시스템
BRPI1007091B1 (pt) sensor de fibra óptica de iluminação lateral, multi paramétrico e com múltiplos pontos sensores.
WO1993006459A1 (fr) Photometre a double longueur d'onde et sonde detectrice a fibre optique
US20070160500A1 (en) Oxygen sensor and measuring method
Mac Craith et al. Fibre optic chemical sensors based on evanescent wave interactions in sol-gel-derived porous coatings: Code: F7
TWI424155B (zh) Surface plasmon resonance sensor
ES2942637T3 (es) Sistema de detección de sustancias fluorescentes
Walt Fiber-optic sensors for continuous clinical monitoring
Lehmann et al. Fiber-optic pH meter using NIR dye
Thompson et al. Component selection for fiber-optic fluorometry
AU2010205741B2 (en) Measuring arrangement for determining at least one parameter of a blood sample
EP1076815A1 (fr) Module entierement base sur fibres optiques destine a un systeme optique de detection chimique
JP2002514758A (ja) 光学的化学検出のためのシステムおよび方法
Grattan et al. Dual wavelength optical fibre sensor for pH measurement
Schultz et al. [32] Optical fiber affinity sensors
Baldini et al. Optical-fibre sensors by silylation techniques
Jones et al. A field-deployable dual-wavelength fiber-optic pH sensor instrument based on solid-state optical and electrical components
MacCraith Optical fiber chemical sensor systems and devices

Legal Events

Date Code Title Description
PUAI Public reference made under article 153(3) epc to a published international application that has entered the european phase

Free format text: ORIGINAL CODE: 0009012

17P Request for examination filed

Effective date: 20001110

AK Designated contracting states

Kind code of ref document: A1

Designated state(s): AT BE CH CY DE DK ES FI FR GB GR IE IT LI LU MC NL PT SE

STAA Information on the status of an ep patent application or granted ep patent

Free format text: STATUS: THE APPLICATION HAS BEEN WITHDRAWN

18W Application withdrawn

Withdrawal date: 20020301