# US 10,765,793 B1 · Ammonia detection in dialysis systems > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 10,765,793 B1 - Document ID: US10765793B1 - Status: Granted - Kind: B1 - Application number: 16/455,276 - Filed: 2019-06-27 - Granted: 2020-09-08 - Earliest claimed: 2019-06-27 - Assignees: Fresenius Medical Care Holdings, Inc. - Applicants: Fresenius Medical Care Holdings, Inc. - Inventors: Harshavardhana Reddy Mallipalli; Philip Scott James; Ethan Lee Zimbra; Kerissa Adams; Troy Dayton; Jon F. Moss - Web page: https://patentgrep.com/patent/US10765793B1 ## CPC - A61M 1/1696: {with dialysate regeneration} - A61M 1/1524: {the interface providing means for actuating on functional elements of the cassette, e.g. plungers} - A61M 1/153: {the cassette being adapted for heating or cooling the treating fluid, e.g. the dialysate or the treating gas} - A61M 1/154: {with sensing means or components thereof} - A61M 1/155: {with treatment-fluid pumping means or components thereof} - A61M 1/1561: {at least one cassette surface or portion thereof being flexible, e.g. the cassette having a rigid base portion with preformed channels and being covered with a foil} - A61M 1/1565: {Details of valves} - A61M 1/1605: {Physical characteristics of the dialysate fluid} - B01D 61/32: Controlling or regulating - G01N 21/78: producing a change of colour - A61M 2205/18: with alarm - A61M 2205/3306: Optical measuring means - A61M 2205/3313: used specific wavelengths - A61M 2205/3324: PH measuring means - A61M 2205/50: with microprocessors or computers - A61M 2205/587: Lighting arrangements - G01N 21/80: Indicating pH value - G01N 2021/775: {Indicator and selective membrane} - G01N 2021/7763: {Sample through flow} - G01N 2021/8557: {Special shaping of flow, e.g. using a by-pass line, jet flow, curtain flow} - A61M: DEVICES FOR INTRODUCING MEDIA INTO, OR ONTO, THE BODY (introducing media into or onto the bodies of animals A61D7/00; means for inserting tampons A61F13/26; devices for administering food or medicines orally A61J; containers for collecting, storing or administering blood or medical fluids A61J1/05); DEVICES FOR TRANSDUCING BODY MEDIA OR FOR TAKING MEDIA FROM THE BODY (surgery A61B; chemical aspects of surgical articles A61L); DEVICES FOR PRODUCING OR ENDING SLEEP OR STUPOR {(Electrotherapy, e.g. producing anaesthesia by the use of alternating or intermittent currents A61N1/36021)} - B01D: SEPARATION (separating solids from solids by wet methods B03B, B03D; by pneumatic jigs or tables B03B; by other dry methods B07; magnetic or electrostatic separation of solid materials from solid materials or fluids, separation by high-voltage electric fields B03C; centrifuges, vortex apparatus B04; presses per se for squeezing-out liquid from liquid-containing material B30B9/02; treatment of water C02F, e.g. softening by ion-exchange C02F1/42; {arrangements of air intake cleaners in gas turbine plants F02C7/05} ; arrangements or mounting of filters in air-conditioning, air-humidification or ventilation F24F13/28) - 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 A spectroscopic detection system includes a sensor configured to reflect light of a first wavelength associated with a presence of a reference substance on the sensor and configured to reflect light of a second wavelength associated with a presence of a monitored substance on the sensor, wherein the monitored substance flows to the sensor from a circulating fluid. The spectroscopic detection system further includes a detector that has first and second channels for respectively receiving the light of the first and second wavelengths reflected from the sensor and one or more processors in electrical communication with the detector and configured to identify an excess condition of the monitored substance with respect to the circulating fluid based on a ratio of a second amount of the light of the second wavelength received at the detector to a first amount of the light of the first wavelength received at the detector. ## Claims ### Claim 1 A spectroscopic detection system, comprising: a sensor configured to reflect light of a first wavelength associated with a presence of a reference substance on the sensor and configured to reflect light of a second wavelength associated with a presence of a monitored substance on the sensor, the monitored substance flowing to the sensor from a circulating fluid; a detector comprising first and second channels for respectively receiving the light of the first and second wavelengths reflected from the sensor; and one or more processors in electrical communication with the detector and configured to identify an excess condition of the monitored substance with respect to the circulating fluid based on a ratio of a second amount of the light of the second wavelength received at the detector to a first amount of the light of the first wavelength received at the detector. ### Claim 2 (depends on 1) The spectroscopic detection system of claim 1, wherein the sensor comprises an acid base indicator that is sensitive to a pH of the monitored substance. ### Claim 3 (depends on 2) The spectroscopic detection system of claim 2, wherein the reference substance is an acidic substance, wherein the sensor is of a first color in an initial state in which the reference substance is present on the sensor and in which the monitored substance is not present on the sensor, and wherein the sensor is of a second color in a subsequent state in which both the reference substance and the monitored substance are present on the sensor. ### Claim 4 (depends on 1) The spectroscopic detection system of claim 1, further comprising one or more lenses arranged to focus the light of the first and second wavelengths reflected from the sensor onto the detector. ### Claim 5 (depends on 1) The spectroscopic detection system of claim 1, further comprising an LED that is configured to radiate broadband light onto the sensor, wherein the sensor is configured to reflect a first portion of the broadband light as the light of the first wavelength and a second portion of the broadband light as the light of the second wavelength. ### Claim 6 (depends on 1) The spectroscopic detection system of claim 1, further comprising a membrane that is permeable to the monitored substance and positioned upstream of the sensor. ### Claim 7 (depends on 1) The spectroscopic detection system of claim 1, further comprising a housing that supports the sensor and that is configured to absorb ambient light. ### Claim 8 (depends on 1) The spectroscopic detection system of claim 1, wherein the sensor is oriented parallel to a bulk flow direction of the circulating fluid and orientated perpendicular to a flow of the monitored substance towards the sensor. ### Claim 9 (depends on 8) The spectroscopic detection system of claim 8, further comprising a flow obstruction that is oriented perpendicular to the bulk flow direction of the circulating fluid and that generates turbulence in a bulk flow of the circulating fluid. ### Claim 10 (depends on 9) The spectroscopic detection system of claim 9, wherein the flow obstruction is configured to increase a velocity of the bulk flow of the circulating fluid. ### Claim 11 (depends on 1) The spectroscopic detection system of claim 1, wherein the sensor comprises a paper material. ### Claim 12 (depends on 1) The spectroscopic detection system of claim 1, further comprising a connector body that houses the sensor and that is configured to be assembled with a fluid line of a fluid cassette, wherein the connector body is arranged to receive a bulk flow of the circulating fluid from a device configured to remove a precursor chemical of the monitored substance from the circulating fluid. ### Claim 13 (depends on 1) The spectroscopic detection system of claim 1, wherein the first amount of the light of the first wavelength comprises a first percent reflectance of a first color associated with the light of the first wavelength, and wherein the second amount of the light of the second wavelength comprises a second percent reflectance of a second color associated with the light of the second wavelength. ### Claim 14 (depends on 1) The spectroscopic detection system of claim 1, wherein the excess condition comprises an increase in a concentration of the monitored substance within the circulating fluid, and wherein the increase in the concentration of the monitored substance corresponds to an increase in a concentration of a precursor chemical of the monitored substance to value that is about equal to or greater than a threshold concentration of the precursor chemical. ### Claim 15 (depends on 1) The spectroscopic detection system of claim 1, wherein the one or more processors are configured to identify the excess condition by determining a moving average of the ratio. ### Claim 16 (depends on 15) The spectroscopic detection system of claim 15, wherein the one or more processors are configured to identify the excess condition by determining a rate of change of the ratio. ### Claim 17 (depends on 16) The spectroscopic detection system of claim 16, wherein the one or more processors are configured to identify the excess condition by comparing the moving average of the ratio to one or more criteria. ### Claim 18 (depends on 1) The spectroscopic detection system of claim 1, wherein the one or more processors are configured to transmit data associated with triggering of an alarm notification upon identification of the excess condition. ### Claim 19 (depends on 1) The spectroscopic detection system of claim 1, wherein the sensor is disposable and the detector is reusable. ### Claim 20 (depends on 1) The spectroscopic detection system of claim 1, wherein the circulating fluid comprises dialysate and the monitored substance comprises ammonia. ### Claim 21 A dialysis system, comprising: a sorbent cartridge configured to remove a precursor substance from dialysate circulating through the dialysis system, the precursor substance being a precursor to a monitored substance; and a spectroscopic detection system for identifying an excess condition of the monitored substance with respect to the dialysate, the spectroscopic detection system comprising: a sensor configured to reflect light of a first wavelength associated with a presence of a reference substance on the sensor and configured to reflect light of a second wavelength associated with a presence of the monitored substance on the sensor, the monitored substance flowing to the sensor from the dialysate, a detector comprising first and second channels for respectively receiving the light of the first and second wavelengths reflected from the sensor, and one or more processors in electrical communication with the detector and configured to identify the excess condition of the monitored substance with respect to the dialysate based on a ratio of a second amount of the light of the second wavelength received at the detector to a first amount of the light of the first wavelength received at the detector. ### Claim 22 A method of detecting a monitored substance within a circulating fluid, the method comprising: flowing the monitored substance to a sensor from the circulating fluid; reflecting light of a first wavelength from the sensor based on a presence of a reference substance on the sensor and reflecting light of a second wavelength from the sensor based on a presence of the monitored substance on the sensor; receiving the light of the first and second wavelengths reflected from the sensor respectively within first and second channels of a detector; and identifying, at one or more processors in electrical communication with the detector, an excess condition of the monitored substance with respect to the circulating fluid based on a ratio of a second amount of the light of the second wavelength received at the detector to a first amount of the light of the first wavelength received at the detector.