Method and apparatus for measuring lipid peroxidation in biological fluids and suspensions of tissues

• US 6,372,508 B1
• Filed: 05/19/2000
• Issued: 04/16/2002
• Est. Priority Date: 10/09/1997
• Status: Expired due to Term

• Current Assignee: Carmel Diagnostics Ltd.
• Original Assignee: Lumitest Ltd.
• Inventors: Vladimir, Piuk, Shnizer, Sergey, Resnik, Abraham, Lanir, Amos
• Primary Examiner(s): SNAY, JEFFREY R
• Application Number:
  US09/509,213
• Time in Patent Office: 697 Days
• Field of Search: 436/63, 436/71, 436/172, 436/135, 422/52, 422/82.08, 250/361.C
• US Class Current: 436/63
• CPC Class Codes: G01N 21/71 thermally excited
• CPC Class Codes: G01N 21/76 Chemiluminescence; Bioluminescence
• CPC Class Codes: Y10T 436/206664 Ozone or peroxide

Abstract

The present invention relates to a method and apparatus for measuring the lipid peroxidation extent in biological fluids and suspensions of tissues, in which a specifically prepared lipids containing sample is exposed to heat so as to induce thermo-chemiluminescence light which is emitted by the sample and is enhanced to an amount which can be detected by a special purpose photo detector The measurement of the light allows to conclude about the content of peroxides and subsequently to obtain accurate assessment of lipid peroxidation .

Claims

1. A method of measuring lipid peroxidation in a biological sample, in which the sample is heated to induce therein thermochemical luminescence (TCL) and in which said TCL is measured, said method comprising the steps of:

a) providing a receptacle having a substantially flat bottom for receiving said sample;

b) introducing said the sample into said receptacle;

c) bringing said receptacle into contact with a heat sink member, said heat sink member is made of material having high thermal conductivity;

d) imparting motion to said receptacle to distribute said sample over the bottom of said receptacle in a substantially homogeneous manner;

e) drying said sample without causing freezing thereof by subjecting said sample to a reduced pressure and without adding heat for a period of time sufficient to remove the liquid from the sample and form a continuous layer of dry solid;

f) heating said dry solid layer to a temperature sufficient for inducing TCL therein; and

g) sensing said TCL and measuring thereof for a period of time sufficient for establishing a stable correlation between TCL intensity and time.

2. A method as defined in claim 1, in which said receptacle comprises a disposable vessel made of thin aluminum foil and said heat sink member is an aluminum plate.

3. A method as defined in claim 1, in which a reciprocating motion is imparted to said receptacle for at least 40 seconds to form a continuous layer having thickness 0.3-0.5 mm.

4. A method as defined in claim 1, in which said reduced pressure does not exceed 2 mbar and said drying time does not exceed 10 minutes.

5. A method as defined in claim 1, in which heating said dry solid is carried out at a temperature of at least 60°

C.

6. A method as defined in claim 1, in which measuring of said TCL is carried out by measuring the intensity thereof in the range of 400-600 nm for at least 300 seconds.

7. An apparatus for measuring lipid peroxidation in a biological sample in which the sample is heated so as to induce therein thermochemical luminescence (TCL) and said TCL is measured, said apparatus comprising:

a drying chamber for receiving a receptacle with the sample introduced therein, said drying chamber is in communication with an evacuating means for evacuating liquid from the sample without freezing thereof and without adding heat to the sample, said drying chamber comprises

i) a heat sink member made of a high thermal conductivity material, and

ii) driving means for imparting motion to said receptacle;

a heating chamber provided with a means for heating said receptacle and a means for measuring the TCL of said dried sample;

a data presentation unit for presenting the TCL measurements; and

a control and date processing unit for controlling the driving means, the evacuating means, the heating means, the means for measuring the TCL and the data presentation unit.

8. The apparatus as defined in claim 7, in which said receptacle comprises a disposable vessel made of aluminum foil, and said heat sink member comprises an aluminum plate, said plate having a depression for receiving the receptacle therein.

9. The apparatus as defined in claim 7, in which said evacuating means comprises a vacuum pump for generating reduced pressure within the drying chamber.

10. The apparatus as defined in claim 8, in which said plate is supported by elastic tubular elements connecting said plate with the bottom of the drying chamber, and said driving means comprises a motor and a cam.

11. The apparatus as defined in claim 7, in which said heating means comprises transistor and temperature sensor and said means for measuring of the TCL comprises photo-electronic multiplier.