Processing method for the long-term stabilization of biological red blood cell volume

• US 20060194191A1
• Filed: 12/30/2005
• Published: 08/31/2006
• Est. Priority Date: 02/25/2005
• Status: Active Grant

• Current Assignee: Shenzhen Mindray Bio-Medical Electronics Co., Ltd. (Excelsior Union Ltd.)
• Original Assignee: Shenzhen Mindray Bio-Medical Electronics Co., Ltd. (Excelsior Union Ltd.)
• Inventors: Zhang, Hui, Liu, Mulong, Xu, Zuyue
• Granted Patent: US 8,029,978 B2
• Time in Patent Office: Days
• US Class Current: 435/2
• CPC Class Codes: A01N 1/02 Preservation of living parts
• CPC Class Codes: A01N 1/0226 Physiologically active agents, i.e. substances affecting physiological processes of cells and tissue to be preserved, e.g. anti-oxidants or nutrients
• CPC Class Codes: Y10T 436/101666 Particle count or volume standard or control [e.g., platelet count standards, etc.]
• CPC Class Codes: Y10T 436/107497 Preparation composition [e.g., lysing or precipitation, etc.]
• CPC Class Codes: Y10T 436/2525 Stabilizing or preserving

Abstract

The present invention relates to a processing method for long-term stabilization of biological red blood cell volume. The red blood cells can be further used in reference materials and calibrators of a hematology analyzer. The method of the present invention comprises contacting the sample with a solution comprising a membrane-fixation reagent and an aldehyde for a processing period to terminate or slow down the red blood cell metabolism. It is provided by experiments that such process enables the volume of the red blood cells to be stable in a period over 120 days.

Claims

1. A processing method for the long-term stabilization of biological red blood cell volume, comprising contacting a red blood cell (RBC) sample with a processing solution comprising a membrane-fixation reagent and an aldehyde, wherein the membrane-fixation reagent is selected from a group consisting of manganic acid or metal salts thereof, chromic acid or metal salts thereof, picric acid and salts of cadmium, and wherein the aldehyde is selected from a group consisting of formaldehyde, paraformaldehyde, glutaraldehyde, olefine aldehyde and combinations thereof.

2. The method according to claim 1, wherein the membrane-fixation reagent is potassium dichromate or cadmium chloride.

3. The method according to claim 1, wherein the aldehyde is formaldehyde, paraformaldehyde, or a mixture of formaldehyde and glutaraldehyde.

4. The method according to claim 1, wherein the contacting is carried out at room temperature.

5. The method according to claim 1, wherein the contacting of the RBC sample with the processing solution lasts for a period of between 30 minutes and 3 hours.

6. The method according to claim 1, wherein the concentration of the membrane-fixation reagent in the processing solution is 0.02%-0.5% (w/v) and the concentration of the aldehyde is 0.02%-0.3% (v/v).

7. The method according to claim 6, wherein the processing solution comprises 0.05% (w/v) potassium dichromate and 0.08% (v/v) formaldehyde.

8. The method according to claim 6, wherein the processing solution comprises 0.05% (w/v) cadmium chloride, 0.05% (v/v) formaldehyde and 0.02% (v/v) glutaraldehyde.

9. The method according to claim 1, wherein the processing solution is obtained by adding the membrane-fixation reagent and the aldehyde to a common nutrient-free buffer system such as citrate buffer, phosphate-buffered saline (PBS) and Tris buffer, and the final pH is between 7.1 and 8.5.

10. The method according to claim 9, wherein a nutrient-free buffer system comprising sodium citrate (1-10 g/L), sodium azide (1-5 g/L), potassium chloride (0.1-5 g/L), sodium sulfate (0.5-2 g/L), penicillin (0.1-2 g/L), streptomycin (0.1-2 g/L), neomycin (0.1-2 g/L), sodium chloride (1-8 g/L) and agarose or cellulose (0.2-10 mg/L) is used.

11. The method according to claim 1, wherein the biological RBCs are human RBCs, animal RBCs, or a mixed sample comprising RBCs from multiple species.