Unattended liquid sample monitoring and liquid sample storage system

• US 6,553,319 B1
• Filed: 07/10/2001
• Issued: 04/22/2003
• Est. Priority Date: 07/10/2001
• Status: Active Grant

• Current Assignee: Southwest Research Institute
• Original Assignee: Southwest Research Institute
• Inventors: Helffrich, Jerome A., McBride, William G. Jr.
• Primary Examiner(s): Barlow, John
• Assistant Examiner(s): WASHBURN, DOUGLAS N
• Application Number:
  US09/902,022
• Time in Patent Office: 651 Days
• Field of Search: 702/23, 702/25, 731/94.E, 204/153.1, 204/406, 128/632, 250/343, 324/29, 324/321, 324/694, 340/853.3, 364/496, 364/497, 436/52, 600/309
• US Class Current: 702/25
• CPC Class Codes: G01N 1/18 with provision for splitting samples into portions G01N1/12, G01N1/14 take precedence; fraction-collection apparatus for chromatography B01D15/08
• CPC Class Codes: G01N 2001/1093 Composite sampling; Cumulative sampling
• CPC Class Codes: G01N 33/18 Water
• CPC Class Codes: G01N 33/54373 involving physiochemical end-point determination, e.g. wave-guides, FETS, gratings

Abstract

An unattended, self-calibrating, microprocessor controlled, electromechanical liquid sample acquisition, analysis and storage system is contained in a sealed evacuated housing. Liquid is drawn by suction into the sealed evacuated housing where it passes through a microfluidic manifold assembly to be brought into contact with signal producing liquid condition sensors. A marker solution is used to demarcate samples of liquid stored in an evacuated capillary. The microprocessor stores the signals produced by the liquid condition sensors and allows for cross-referencing the stored signals with the stored liquid samples in the capillary.

Claims

1. A liquid sample acquisition storage device comprising:

an evacuated housing, said housing having an inlet in liquid connection with a microfluidic manifold assembly, said microfluidic manifold assembly containing at least one signal producing liquid analyzing sensor;

a reservoir in liquid connection with said microfluidic manifold assembly;

a microprocessor assembly having means for both storing the signals obtained from said signal producing liquid analyzing sensor and controlling the flow of a marker solution from a pressurized source of marker solution into the liquid sample; and

at least one capillary for storing liquid samples.

2. The liquid sample acquisition and storage device as defined in claim 1, further including a filter in said inlet.

3. The liquid sample acquisition and storage device as defined in claim 1, wherein said microfluidic manifold assembly further includes at least one well in which said at least one signal producing liquid analyzing sensor is positioned.

4. The liquid sample acquisition and storage device as defined in claim 1, wherein said signal producing liquid analyzing sensor is selected from a group including electrochemical, optical, acoustical, electrical or magnetic sensors.

5. The liquid sample acquisition and storage device as defined in claim 1, wherein said liquid is analyzed for temperature, pressure, pH, the presence of chloride ions, the presence of K+ ions, and the presence of NO₃ ions.

6. The liquid sample acquisition and storage device as defined in claim 1, wherein said signal producing liquid analyzing sensors include at least one biologically active sensor.

7. The liquid sample acquisition and storage device as defined in claim 6, wherein said at least one biologically active sensor is a surface acoustic wave resonator whose face is sensitized with either antigens or DNA fragments.

8. The liquid sample acquisition and storage device as defined in claim 1, wherein said reservoir is constructed and arranged to flush out said inlet of said evacuated housing.

9. The liquid sample acquisition and storage device of the present invention as defined in claim 1, wherein said reservoir is filled with a reference liquid of known composition to pass through said microfluidic manifold assembly to said signal producing liquid analyzing sensor to calibrate said signal producing liquid analyzing sensor.

10. The liquid sample acquisition and storage device as defined in claim 1, wherein said capillary is stored on a reel within said housing.

11. The liquid sample acquisition and storage device as defined in claim 1 wherein the microprocessor assembly is programmed to correlate the stored signals in said microprocessor assembly with a sample stored in said evacuated capillary.

12. The liquid sample acquisition and storage device as defined in claim 1, wherein said evacuated capillary permits the examination of the stored liquid samples using fluorescence spectroscopy.

13. The liquid sample acquisition and storage device as defined in claim 1, wherein the entry of liquid into said evacuated housing is controlled by said microprocessor assembly.

14. The liquid sample acquisition and storage device as defined in claim 1, further including means for real time monitoring of the output of said signal producing liquid condition sensors.

15. A method for monitoring and storing liquid samples at a remote location comprising the steps of:

drawing a flow of liquid into a sealed housing by vacuum within the housing;

directing said flow of liquid through a microfluidic manifold assembly;

contacting said liquid with at least one signal producing liquid condition sensor;

storing the signals produced by said at least one signal producing liquid condition sensor in a microprocessor assembly; and

directing said liquid samples and a marker liquid into a capillary.

16. The method of claim 15, further comprising the step of injecting a marker solution into said flow of liquid to separate samples of said liquid.

17. The method of claim 16, wherein said marker solution is also used to flush out said inlet of said evacuated housing.

18. The method of claim 16, wherein said marker solution is used to calibrate said signal producing liquid condition sensors.

19. The method of claim 16, wherein said evacuated capillary is stored on a reel within said sealed housing.

20. The method of claim 16, wherein the insertion of said marker solution into said flow of liquid is triggered by the elapse of a specified time period.

21. The method of claim 16, wherein the insertion of said marker solution into the flow of liquid is triggered by exceeding a predetermined signal level produced by said at least one signal producing liquid condition sensor.

22. The method of claim 15, wherein said signal producing liquid condition sensors are selected from a group including electrochemical, optical, acoustical, electrical or magnetic sensors.

23. The method of claim 15, wherein said liquid conditions monitored are selected from a group including temperature, pressure, pH, the presence of chloride ions, the presence of K+ ions, and the presence of NO₃ ions.

24. The method of claim 15, wherein said signal producing liquid condition sensors include at least one biologically active sensor.

25. The method of claim 15, wherein the step of drawing the liquid into said housing is continuous.

26. The method of claim 15, further comprising the step of correlating the stored signals in said microprocessor assembly with said liquid samples stored in the capillary.

27. The method of claim 15, further comprising the use of the stored signals to identify regions of the liquid in the capillary.

28. The method of claim 15, wherein said evacuated capillary permits the examination of said stored liquid samples using fluorescence spectroscopy.

29. The method of claim 15, further comprising the step of controlling the entry of said flow of liquid into the housing with the microprocessor assembly.

30. The method of claim 20, further comprising the step of monitoring, in real time, the output of said signal producing liquid condition sensors.