Continuous on-line blood monitoring system

• US 4,974,592 A
• Filed: 11/14/1988
• Issued: 12/04/1990
• Est. Priority Date: 11/14/1988
• Status: Expired due to Fees

• Current Assignee: American Sensor Systems Corporation
• Original Assignee: American Sensor Systems Corporation
• Inventors: Branco, Flavio S. C.
• Primary Examiner(s): Cohen, Lee S.
• Application Number:
  US07/270,960
• Time in Patent Office: 750 Days
• Field of Search: 128/635, 204/403, 204/409, 204/411, 204/416
• US Class Current: 600/348
• CPC Class Codes: A61B 5/15003 for venous or arterial blood
• CPC Class Codes: A61B 5/150221 Valves
• CPC Class Codes: A61B 5/150229 Pumps for assisting the blood sampling
• CPC Class Codes: A61B 5/150755 Blood sample preparation for further analysis, e.g. by separating blood components or by mixing
• CPC Class Codes: A61B 5/153 Devices specially adapted for taking samples of venous or arterial blood, e.g. with syringes
• CPC Class Codes: A61B 5/155 Devices specially adapted for continuous or multiple sampling, e.g. at predetermined intervals devices loaded with multiple lancets simultaneously A61B5/15146
• CPC Class Codes: A61B 5/157 Devices characterised by integrated means for measuring characteristics of blood
• CPC Class Codes: G01N 27/414 Ion-sensitive or chemical field-effect transistors, i.e. ISFETS or CHEMFETS
• CPC Class Codes: G01N 33/49 Blood chemical methods for determining blood cell populations G01N33/5094; chemical analysis of blood groups or blood types G01N33/80
• CPC Class Codes: G01N 35/08 using a stream of discrete samples flowing along a tube system, e.g. flow injection analysis

Abstract

A continuous on-line blood monitoring system for determining the ionic concentrations of certain ions within blood is disclosed. By use of a synchronized valving mechanism within the device, as well as locating the amplification electronics away from the sensor elements, a relatively small, but highly efficient analyzing system is provided.

Claims

1. A continuous on-line blood monitoring system for measuring ionic concentrations comprising:

at least one ion concentration sensor device;

a first feed line for receiving analyte connected to said sensor device;

an analyte pinch/cylinder valve actuator operatively connected to said analyte feed line;

a second feed line for receiving a solution to generate an ionic baseline connected to said sensor device;

an ionic baseline pinch/cylinder valve actuator operatively connected to said second feed line;

pumping means for activating and deactivating said analyte pinch/cylinder valve actuator and said ionic baseline pinch/cylinder valve actuator, said pumping means operatively connected to said analyte pinch/cylinder valve actuator and said baseline pinch/cylinder valve actuator;

means for alternating the operation of said analyte pinch/cylinder valve actuator and said baseline pinch/cylinder valve actuator operatively connected to said pumping means; and

means for amplifying and sending signals generated by the ionic concentration of said analyte operatively connected to said sensor device.

2. The system of claim 1 wherein said sensor device is a ChemFET.

3. The system of claim 1 wherein said sensor device comprises a sensor plate having on one side thereof at least one sensor electrode having an active area covered with an ion selective membrane and connected to an extended area, said extended area in turn connected to a sensor terminal, and a reference electrode on the side opposite said sensor plate.

4. The system of claim 3 wherein said plate is of a glasslike material of low porosity, inert to both said analyte and a reference solutions.

5. The system of claim 4 wherein said sensor plate is quartz.

6. The system of claim 3 wherein said extended area is overlaid with a coating of silver/palladium.

7. The system of claim 3 wherein said active area is approximately two square millimeters.

8. The system of claim 3 wherein said selective membrane is selective to a specific ion.

9. The system of claim 3 wherein said reference electrode has in the central portion thereof an orifice having a diameter of between approximately 500 and 2,000 microns, preferably 1,000 microns.

10. The system of claim 9 wherein said reference electrode is of a noble metals.

11. The system of claim 1 wherein said means for amplifying and sending signals generated by the ionic concentration of said analyte is a fiberoptic cable.