Method to determine the sedimentation of blood and relative device

• US 5,827,746 A
• Filed: 03/08/1996
• Issued: 10/27/1998
• Est. Priority Date: 03/15/1995
• Status: Expired due to Term

• Current Assignee: Nuclear Médica SpA
• Original Assignee: SIRE Analytical Systems SRL
• Inventors: Duic, Giovanni Battista
• Primary Examiner(s): WALLENHORST, MAUREEN
• Application Number:
  US08/613,233
• Time in Patent Office: 963 Days
• Field of Search: 436/63, 436/70, 436/164, 436/165, 422/68.1, 422/73, 422/82.05, 422/82.09, 435/2, 435/288.7, 435/808, 356/39, 73/61.63, 73/61.64, 73/61.65, 73/61.66, 73/61.68, 73/61.69
• US Class Current: 436/70
• CPC Class Codes: G01N 15/042 by centrifuging and investigating centrifugates centrifuges per se B04B
• CPC Class Codes: G01N 15/05 in blood
• CPC Class Codes: G01N 33/491 by separating the blood components G01N15/05 takes precedence

Abstract

Method and apparatus to determine the sedimentation of blood. A blood sample is taken, and an anti-coagulant substance is added. The sample is homogenized. The method includes a step of measuring an optical density, or absorbance, of the sample as a function of time and without waiting for the formation of a plasma/corpuscle interface to obtain an optical density measurement. The measurements are carried out at any fixed point of a reading container which contains a micro-volume of blood. The inner diameter of the containing chamber ensures a linear relationship between the optical density and the number of corpuscles present. Finally, the optical density measurement is processsed to obtain a speed of sedimentation.

Claims

1. Method to determine the speed of sedimentation of corpuscles present in a sample of blood, the method being carried out on a sample consisting of blood to which any anti-coagulant substance has been added and which is suitably homogenized, the method comprising the steps of measuring an optical density, or absorbance, of a homogenized sample of blood to which an anticoagulant has been added, as a function of time and without waiting for the formation of a plasma/corpuscle interface to obtain an optical density measurement, the measuring step being carried out at any fixed point of a reading container defining a containing chamber of an inner diameter of between 0.1 and 2.0 mm which contains a micro-volume of the sample of blood, the inner diameter of the containing chamber ensuring a linear relationship between the optical density and the number of corpuscles present in the sample of blood, and wherein the reading container is subjected to centrifuging during the measuring step;

and processing said optical density measurement to obtain a speed of sedimentation of corpuscles in the blood sample.

2. Method as in claim 1, wherein said method enables a value of a corpuscular mass in the sample of blood to be identified.

3. Method as in claim 1, in which during the centrifuging the sample undergoes an acceleration between 2 and 20 g.

4. Method as in claim 3, in which the centrifuging takes place about an axis perpendicular to a plane of positioning of the reading container.

5. Method as in claim 3, in which during the centrifuging the sample of blood undergoes an acceleration of between 7 to 8 g.

6. Method as in claim 1, which is independent of the type of anti-coagulant substance added to the sample of blood.

7. Method as in claim 1, wherein said method is governed by a programming, processing and control assembly for an automatic determination of the speed of sedimentation.

8. Method as in claim 1, wherein said method enables the sedimentation of a plasma part of the sample of blood to be measured in an analytical and quantitative manner.

9. Method to determine the speed of sedimentation of corpuscles present in a sample of blood, the method being carried out on a sample of blood to which an anti-coagulant has been added, comprising the steps of:

homogenizing and adding an anti-coagulant to a sample of blood and feeding the sample of blood to be analyzed into a reading container;

centrifuging the sample of blood about an axis perpendicular to a plane of positioning of the reading container;

emitting and monitoring an electromagnetic radiation at a fixed point of the reading container holding the blood sample, while centrifuging to measure development, over a period of time, of an optical density of the sample of blood analyzed without waiting for the formation of a plasma/corpuscle interface to obtain the optical density measurement;

processing optical density signals as a function of a period of time;

displaying speed of sedimentation results obtained from the processed optical density signals; and

discharging the analyzed sample of blood from the reading container.

10. Method as in claim 9, which further comprises a step of comparison of optical density signals with previously stored measurements associated with known pathologies, wherein said step of comparison is used to determine inflammatory pathologies.

11. Device for determining the speed of sedimentation of corpuscles in blood, comprising, at least one means for feeding a homogenized sample of blood to which an anti-coagulant has been added to a reading container set in rotation about an axis perpendicular to a plane of positioning of the reading container by a means for centrifuging, an emitting and monitoring assembly to emit and monitor electromagnetic radiations, wherein said assembly is positioned at a fixed point perpendicular to a plane of positioning of the reading container, a means for acquiring optical density data and a programming, processing and control assembly;

wherein the reading container defines a containing chamber having an inner diameter between 0.1 and 2 mm and wherein optical density data measurements are acquired without waiting for a plasma/corpuscle interface to form in the sample of blood.

12. Device as in claim 11, in which the reading container comprises an inlet and an outlet for feeding and discharge of the sample of blood.

13. Device as in claim 11, in which the reading container extends, without a break of continuity, from a feed to a discharge of the sample of blood.

14. Device as in claim 11, in which the emitting and monitoring assembly and the means to acquire optical density data enables the development, over a period of time, of the optical density of the sample of blood, wherein said development over time is correlated with the speed of sedimentation (VES).

15. Device as in claim 11, in which the emitting and monitoring assembly is positioned as desired along an axis of the reading container.

16. Device as in claim 11, in which the reading container has a reflecting surface, and the emitting and monitoring assembly has emitting means and monitoring means positioned on a same side of the plane of positioning of the reading container.

17. Device as in claim 11, in which the rotation about an axis perpendicular to the plane of positioning of the reading container by the means for centrifuging is performed by a centrifuge and the centrifuge can be adjusted as desired as a function of a desired duration of analysis.

18. The device of claim 17, wherein a gradient of acceleration and a final value of acceleration can be adjusted in said centrifuge.

19. Device as in claim 11, which subjects the sample of blood to a centrifugal acceleration of between 2 and 20 g.

20. Device as in claim 19, which subjects the sample of blood to a centrifugal acceleration of between 7 to 8 g.

21. Device as in claim 11, in which, the emitting and monitoring assembly and the means to acquire optical density data can be adjusted as desired.

22. Device as in claim 11, in which the programming, processing and control assembly is associated with a bank of reference data.

23. Device as in claim 11, wherein said device is further coupled hydraulically and electronically to other apparatuses for performance of other analyses of blood.

24. Device as in claim 23, wherein the other analyses of blood performed is a haemochromocytometric examination.

25. Device as in claim 11, further comprising a means to flush a suitable solution for washing and sterilization of the reading container between one analysis and a subsequent analysis.

26. The device of claim 11, wherein the reading container defines a containing chamber having an inner diameter of 1 mm.