Glucose level test apparatus

• US 4,105,522 A
• Filed: 04/21/1975
• Issued: 08/08/1978
• Est. Priority Date: 06/15/1973
• Status: Expired due to Term

• Current Assignee: Mankind Research Foundation, Inc.
• Original Assignee: John L. Yoscak, Robert M. Friedenberg, Stephen E. Noren
• Inventors: Noren, Stephen E., Friedenberg, Robert M., Yoscak, John L.
• Primary Examiner(s): Tung, T.
• Application Number:
  US05/570,092
• Time in Patent Office: 1,205 Days
• Field of Search: 204/1 T, 204/1 E, 204/195 R, 204/195 B
• US Class Current: 204/403.01
• CPC Class Codes: G01N 27/3273 Devices therefor, e.g. test element readers, circuitry details not specific to biochemical electrodes G01N33/4875

Abstract

Method, apparatus and test compositions are provided for rapid, accurate test of concentration levels of various components of body fluids, particularly the glucose level in saliva, by oxidizing the test sample under controlled conditions with an excess of oxidizing agent and measuring the level of the component such as glucose in the body fluid as redox potential in millivolts of a primary cell in which the residual oxidizing solution is the electrolyte.

Claims

1. Apparatus for measuring the glucose level of body fluids comprising means for heating and reacting a small measured liquid quantity of a solution comprising a test fluid body sample and oxidizing agent disposed in a container in quantity to oxidize said sample to a fully oxidized form and leave a measurable remainder of oxidizing agent in said solution, means for controlling the temperature and timing of the oxidation reaction of said solution including means to trigger a timing circuit to hold the temperature at a selected value for a predetermined period, metallic electrodes suspended into contact with the liquid in said container as a primary cell, each of said electrodes having a surface area in direct liquid contact with the said oxidized body fluid whereby to pass the current developed in the reaction product solution electrolytically to said electrodes, means for setting the output circuit of said cell to null voltage and means for measuring the electrical output of said cell in millivolts as redox potential developed in said cell by said oxidized body fluid reaction products.

2. Apparatus as defined in claim 1 wherein the electrodes are of different materials.

3. The apparatus as defined in claim 1 including a potentiometer means for setting said null voltage.

4. The apparatus as defined in claim 3 wherein the potentiometer means for adjusting the circuit to substantially null voltage is operative upon a low voltage with a spread of less than about 11/2 volts.

5. The apparatus as defined in claim 1 including a household circuit source, a rectifier and a transformer therein to convert the said household current to low DC voltage of less than about ten volts, and a potentiometer in said circuit capable of adjusting said low voltage output to less than about 11/2 volts.

6. The apparatus as defined in claim 1 having means for measuring the electrical output in a millivolt meter calibrated to read in level of glucose contained in the body fluid sample which has been tested.

7. The apparatus as defined in claim 1 comprising a housing, a millivolt meter mounted for visible exhibit of its output reading in large indicia, a test chamber in said housing sized to receive and support a test container with said electrodes mounted therein, a closure for said chamber, said heating means surrounding said chamber for controlling the temperature thereof, and circuit means disposed within said housing for supply of current to said heating means, and for interconnecting said electrode and the millivoltage read-out thereof.

8. In an apparatus for measuring the glucose level of body fluids, as defined in claim 1, further comprising a plastic body having said electrodes sealed therein, said electrodes each having one end of measured surface area extending from said plastic body for contact with a test fluid whose redox potential is to be measured, and extending outward of the opposite end of said plastic body as a connector plug for easy fastening and separating said electrodes from contacts carried by the apparatus.

9. An apparatus for measurement of glucose level of body fluids comprising means for heating and reacting a small quantity of test solution comprising a test sample and oxidizing agent disposed in a container at a controlled temperature, a housing, a millivolt meter mounted for visible exhibit of its output reading in large indicia, a test chamber in said housing sized to receive and support a test container with metallic electrodes mounted therein, a closure for said chamber, said heating means surrounding said chamber for controlling the temperature thereof including means to trigger a timing circuit to hold the temperature at a selected value for a predetermined period, and circuit means disposed within said housing for supply of current to said heating means, and interconnecting said electrodes and the millivolt read-out thereof, a household circuit source, a rectifier and transformer therein to convert the said household current to low DC voltage of less than about ten volts, and a potentiometer in said circuit capable of adjusting said low voltage output to less than about 11/2 volts, said electrodes being suspended into contact with the liquid in said container as a primary cell.

10. The apparatus as defined in claim 9 further including a timer in said circuit making and breaking the circuit to said heater in measured periods, a temperature sensor responsive to the temperature in said test solution controlling said heating circuit and timer to provide heat at the sensed temperature for an exact short time period.

11. In an apparatus for measuring the glucose level of body fluids, a housing enclosing a test chamber, means surrounding said test chamber for controlled heating thereof, an electrode assembly comprising a plastic body having separate metallic electrodes sealed therein, said metallic electrodes each having one end of measured surface area extending from said plastic body for contact with a test fluid whose redox potential is to be measured, and extending outward of the opposite end of said plastic body as a connector plug for easy fastening and separating said electrode assembly from contacts, a container disposed within said test chamber having a wide mouth for receiving a test fluid body sample and oxidizing agent and said plastic body, said electrode assembly being disposed in said container, hinged cover means in said housing covering said test chamber and having electrical jack-type contacts for receiving the contacts of said connection plug extending from said electrode assembly completing the circuit to and supporting the outward extending ends of said electrode assembly from the liquid test solution of said container, said electrode assembly further containing a heat sensor suspended in contact with said test solution, a millivolt meter calibrated to read in terms of glucose content of the oxidizing body sample in circuit with the said electrodes, electrical circuit means including a rectifier and transformer for reducing household current to small DC voltage for said electrodes, and to supply current to said heating means, and an electrical timer in the said circuit for timing the heating of said sample at the temperature controlled by said sensor.