# US 7,608,460 B2 · Fluorescent pH detector system and related methods > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 7,608,460 B2 - Document ID: US7608460B2 - Status: Granted - Kind: B2 - Application number: 11/207,580 - Filed: 2005-08-19 - Published: 2006-03-09 - Granted: 2009-10-27 - Earliest claimed: 2004-08-19 - Assignees: Blood Cell Storage, Inc. - Inventors: Michael W. Reed; Steven J. Geelhood; Paul C. Harris; Randy D. Pfalzgraf - Web page: https://patentgrep.com/patent/US7608460B2 ## CPC - G01N 21/645: {Specially adapted constructive features of fluorimeters} - G01N 21/6428: {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)} - 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)} - G01N 21/80: Indicating pH value - G01N 2021/7786: {Fluorescence} - G01N: INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES (measuring or testing apparatus or processes other than immunoassay, involving enzymes or microorganisms C12M, C12Q) ## Abstract Fluorescent pH detector and methods for measuring pH using the fluorescent pH detector. ## Claims ### Claim 1 A system for measuring pH, comprising: (a) a light source for exciting a fluorescent species, wherein the fluorescent species has a first emission intensity at a first emission wavelength and a second emission intensity at a second emission wavelength; (b) a first emission detector for measuring the first emission intensity; (c) a second emission detector for measuring the second emission intensity; (d) an excitation lightguide for transmitting excitation light from the light source to the fluorescent species, wherein the lightguide comprises a first terminus proximate to the light source and a second terminus distal to the light source; (e) a first emission lightguide for transmitting emission from the fluorescent species to the first emission detector, wherein the lightguide comprises a first terminus proximate to the detector and a second terminus distal to the detector; (f) a second emission lightguide for transmitting emission from the fluorescent species to the second emission detector, wherein the lightguide comprises a first terminus proximate to the detector and a second terminus distal to the detector; (g) a probe housing the distal termini of the excitation lightguide, first emission lightguide, and second emission light guide; and (h) an assembly for receiving the probe, the assembly comprising: (i) a housing for receiving the probe, wherein the housing is adapted for receiving the probe at a first end and terminating with a window at the second end, the window being transparent to the excitation and the emission light, (ii) a tip member reversibly connectable to the housing's second end, wherein the tip member is adapted to receive liquid from a sample to be measured, and (iii) a fluorescent species immobilized on a substrate intermediate the tip member and the window, wherein the fluorescent species immobilized on the substrate is in liquid communication with the sample during the measurement, and wherein the window physically isolates the probe member from the fluorescent species immobilized on the substrate. ### Claim 2 (depends on 1) The system of claim 1, wherein the light source is a light-emitting diode. ### Claim 3 (depends on 1) The system of claim 1, wherein the first and second detectors are photodiodes. ### Claim 4 (depends on 1) The system of claim 1, wherein the excitation lightguide, the first emission lightguide, and the second emission lightguide are optical fibers. ### Claim 5 (depends on 1) The system of claim 1, wherein the housing comprises a tapered tube terminating with the window. ### Claim 6 (depends on 1) The system of claim 1, wherein the fluorescent species comprises a seminaphthofluorescein/human serum albumin conjugate. ### Claim 7 (depends on 1) The system of claim 1, wherein the tip member comprises a spike for puncturing a sealed vessel. ### Claim 8 (depends on 1) The system of claim 1, wherein the probe comprises one or more optical fibers. ### Claim 9 (depends on 1) The system of claim 1, wherein the fluorescent species is selected from the group consisting of a naphthofluorescein compound and a seminaphthorhodamine compound. ### Claim 10 (depends on 9) The system of claim 9, wherein the naphthofluorescein compound is selected from the group consisting of a seminaphthofluorescein compound and a carboxynaphthofluorescein compound. ### Claim 11 (depends on 1) The system of claim 1, wherein the fluorescent species is a seminaphthofluorescein compound selected from the group consisting of 5′(and 6′)-carboxy-3,10-dihydroxy-spiro[7H-benzo[c]xanthene-7,1′(3′H)-isobenzofuran]-3′-one and 2-(2-chloro-3-hydroxy-9-carboxyethyl-10-oxo-10H-benzo[c]xanthene-7-yl)benzoic acid. ### Claim 12 (depends on 1) The system of claim 1, wherein the fluorescent species immobilized on a substrate comprises a conjugate of a fluorescent species and a macromolecule. ### Claim 13 (depends on 12) The system of claim 12, wherein the macromolecule is an albumin. ### Claim 14 (depends on 1) The system of claim 1, wherein the fluorescent species immobilized on a substrate comprises a seminaphthofluorescein/human serum albumin conjugate. ### Claim 15 (depends on 1) The system of claim 1, wherein the sample comprises blood or a blood product. ### Claim 16 (depends on 1) The system of claim 1, wherein the sample is contained within a sealed vessel.