Blood analyzer and blood analyzing method

• US 20070109530A1
• Filed: 11/15/2006
• Published: 05/17/2007
• Est. Priority Date: 11/15/2005
• Status: Active Grant

• Current Assignee: Sysmex Corporation
• Original Assignee: Sysmex Corporation
• Inventors: Hamada, Yuichi, Ueno, Kunio
• Granted Patent: US 7,916,280 B2
• Time in Patent Office: Days
• US Class Current: 356/39
• CPC Class Codes: G01N 15/1404 Handling flow, e.g. hydrodynamic focusing
• CPC Class Codes: G01N 15/1459 the analysis being performed on a sample stream
• CPC Class Codes: G01N 2015/016 White blood cells
• CPC Class Codes: G01N 2015/1006 for cytology
• CPC Class Codes: G01N 2015/1019 Associating Coulter-counter and optical flow cytometer [OFC]
• CPC Class Codes: G01N 2015/1479 Using diffuse illumination or excitation
• CPC Class Codes: G01N 2015/1486 Counting the particles
• CPC Class Codes: G01N 21/05 Flow-through cuvettes G01N21/09 takes precedence; handling fluid samples G01N1/10
• CPC Class Codes: G01N 21/53 within a flowing fluid, e.g. smoke
• 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

Abstract

A blood analyzer, comprising a sample preparing part; a flow cell; a light source; a scattered light detector for detecting scattered light from a measurement sample irradiated by the light source; a fluorescence light detector comprising an avalanche photo diode for detecting fluorescence light from the measurement sample irradiated by the light source; a signal processing part for processing a first detection signal from the scattered light detector and a second detection signal from the fluorescence light detector, wherein the signal processing part reduces high frequency noise included in an amplified second detection signal; and a analysis part for classifying white blood cells in the blood into groups based on the first and the second detection signals processed by the signal processing part is disclosed. A blood analyzing method is also disclosed.

Claims

1. A blood analyzer, comprising:

a sample preparing part for preparing a measurement sample comprising a blood, a hemolyzing reagent, and a staining reagent;

a flow cell in which the measurement sample flows;

a light source for irradiating the measurement sample flowing in the flow cell;

a scattered light detector for detecting scattered light from the measurement sample irradiated by the light source;

a fluorescence light detector comprising an avalanche photo diode for detecting fluorescence light from the measurement sample irradiated by the light source;

a signal processing part for processing a first detection signal from the scattered light detector and a second detection signal from the fluorescence light detector, wherein the signal processing part reduces high frequency noise included in an amplified second detection signal; and

a analysis part for classifying white blood cells in the blood into groups based on the first and the second detection signals processed by the signal processing part.

2. The blood analyzer according to claim 1,

wherein the signal processing part comprises a low pass filter for reducing the high frequency noise.

3. The blood analyzer according to claim 2,

wherein the signal processing part further comprises:

a high pass filter for reducing fluctuation of a base line of the amplified second detection signal; and

a base line adjuster for adjusting the base line to a predetermined level.

4. The blood analyzer according to claim 2,

wherein the signal processing part further comprises:

an amplifier for amplifying the second detection signal for obtaining the amplified second detection signal.

5. The blood analyzer according to claim 1,

wherein the analysis part classifies the white blood cells into at least four groups.

6. The blood analyzer according to claim 5,

wherein the analysis part classifies the white blood cells into neutrophils, lymphocytes, monocytes, and eosinocytes.

7. The blood analyzer according to claim 5,

wherein the analysis part classifies the white blood cells into neutrophils, lymphocytes, monocytes, eosinocytes, and basocytes.

8. The blood analyzer according to claim 1,

wherein the signal processing part reduces the high frequency noise such that noise included in the amplified second detection signal is less than 13% of using range of signal level of the amplified second detection signal.

9. The blood analyzer according to claim 1,

wherein the signal processing part reduces the high frequency noise such that noise included in the amplified second detection signal is less than 8% of using range of signal level of the amplified second detection signal.

10. The blood analyzer according to claim 1,

wherein the avalanche photo diode comprises a light detecting round surface having diameter of between about 0.1 mm and about 2 mm.

11. The blood analyzer according to claim 1,

wherein the avalanche photo diode comprises a light detecting rectangle surface having sides of between about 0.1 mm and about 2 mm.

12. The blood analyzer according to claim 1,

wherein the light source comprises a laser diode.

13. The blood analyzer according to claim 12,

wherein the laser diode irradiates red light.

14. The blood analyzer according to claim 1,

wherein the scattered light detector comprises a PIN photodiode for detecting the scattered light.

15. A blood analyzer, comprising:

a sample preparing part for preparing a measurement sample comprising a blood, a hemolyzing reagent, and a staining reagent;

a flow cell in which the measurement sample flows;

a light source for irradiating the measurement sample flowing in the flow cell;

a scattered light detector for detecting scattered light from the measurement sample irradiated by the light source;

a fluorescence light detector comprising an avalanche photo diode for detecting fluorescence light from the measurement sample irradiated by the light source;

a signal processing part for processing a first detection signal from the scattered light detector and a second detection signal from the fluorescence light detector, wherein the signal processing part comprises a low pass filter for reducing high frequency noise included in an amplified second detection signal; and

a analysis part for classifying white blood cells in the blood into groups based on the first and the second detection signals processed by the signal processing part;

wherein a cutoff frequency of the low pass filter is less than frequency Y of following formula;

Y=17.289EXP (−

0.022C)+2

(C represents electric capacity between terminals of the avalanche photo diode).

16. The blood analyzer according to claim 15,

wherein the cutoff frequency of the low pass filter is less than frequency Y of following formula:

Y=10.482EXP (−

0.018C)+1.3

(C represents electric capacity between terminals of the avalanche photo diode).

17. A blood analyzing method, comprising:

preparing a measurement sample comprising a blood, a hemolyzing reagent, and a staining reagent;

exposing the measurement sample to light from a light source;

detecting scattered light from the measurement sample irradiated by the light source;

detecting, by an avalanche photo diode, fluorescence light from the measurement sample irradiated by the light source;

processing a first detection signal obtained from the scattered light;

processing a second detection signal obtained from the fluorescence light, the processing of the second detection signal comprising reducing high frequency noise included in an amplified second detection signal; and

classifying white blood cells in the blood into groups based on a processed first detection signal and a processed second detection signal.

18. The blood analyzing method according to claim 17,

wherein the processing of the second detection signal further comprises:

amplifying the second detection signal for obtaining the amplified second detection signal; and

processing the amplified second detection signal.

19. The blood analyzing method according to claim 18,

wherein the processing of the amplified second detection signal comprises:

the reducing of the high frequency noise;

reducing fluctuation of a base line of the amplified second detection signal; and

adjusting the base line to a predetermined level.

20. The blood analyzing method according to claim 17,

wherein the white blood cells are classified into at least four groups in the classifying step.