HK1171509A - Method for automatic determination of sample analyzed - Google Patents

Description

Method for automatically discriminating test sample

This application is a divisional application of PCT application with application number CN200580025477.4 (international application date: 7/27/2005) entitled "method for automatically discriminating test sample" at the stage of entering the country.

Technical area

The present invention relates to a method for analyzing a test sample, in particular, a method for automatically discriminating a test sample (e.g., a biological fluid, particularly blood) contained in the test sample.

Background

The measurement of specific components in blood, such as antigens, antibodies, proteins, or endocrine substances, is clinically extremely important. In general, plasma or serum is often used as a blood sample. In this case, in order to avoid hemolysis, whole blood is usually subjected to serum/plasma separation as soon as possible. This is because hemocyte components are present in the sample, or hemolysis occurs, for example, in an immunoassay region, which affects an optical system; obstruction of immune response by internal components of blood cells; agglutination of insoluble carriers used in solid phase form by components of the cell membrane; the adsorption is inhibited. Therefore, in general clinical examination, it is common practice to first centrifuge collected whole blood to remove blood cells and use the obtained plasma or serum as an analysis sample.

However, since a special device such as a centrifuge is required for removing blood cells and the time and effort are required, it is desired that whole blood be used as a measurement sample as it is also for doctors in private clinics not equipped with such a device and for urgent examination, and various proposals have been made since long ago.

For example, Japanese patent application laid-open No. H10-48214 (patent document 1) discloses a method of forcedly hemolyzing whole blood by ultrasonic treatment or mixing with a hypotonic solution. Further, japanese patent laying-open No. 6-265554 (patent document 2) discloses a method for analyzing a biochemical component in blood, which includes determining whether or not a sample to be measured contains blood cells, determining whether or not only a measurement item that can be analyzed by the sample to be measured containing blood cells is selected based on a determination result indicating that the sample to be measured contains blood cells, stirring the sample to be measured based on a determination result indicating that only a measurement item that can be analyzed by the sample to be measured containing blood cells is selected, and performing measurement processing based on the sample to be measured after stirring.

However, the forced hemolysis method disclosed in patent document 1 is not a satisfactory method because it not only causes a variation in the degree of hemolysis, but also causes a nonspecific reaction due to an interfering substance such as hemoglobin and a substance derived from a cell nucleus which flow out from the inside of a blood cell to a reaction system, or causes a decrease in a desired immunoreaction and greatly affects the measurement when a test system is an immunological method.

In addition, the method for analyzing biochemical components in blood disclosed in patent document 2 described above hardly describes the type of a test sample, that is, a method for determining whether or not a test sample contains blood cells. Only the case where a sample type discriminating unit composed of a transmission type optical sensor or the like is disposed above a cuvette in which a reagent, a sample to be measured, a diluent, and the like are sealed in advance is disclosed. In the case of a blood cell-containing sample to be measured, there is no description at all about a specific discrimination procedure or discrimination standard, except that the sample to be measured is stirred to compensate for hematocrit.

Patent document 1: japanese unexamined patent publication No. Hei 10-48214

Patent document 2: japanese unexamined patent publication No. 6-265554

Disclosure of Invention

The present invention provides a method for automatically discriminating the type of a test sample by a measurer without inputting the type of the test sample into an analyzer or performing a setting operation in advance in a general-purpose automatic analyzer capable of analyzing not only plasma or serum but also whole blood as the test sample. Further, the present invention is also intended to provide a method for detecting that a test sample has not been placed in a test sample, while not only discriminating the type of the test sample. Further, the present invention provides a method for simultaneously detecting the missing of a dispensing tip in an automatic analyzer having a dispensing tip attached thereto.

The above problem can be solved according to the present invention by a method of discriminating the type of a test sample (preferably, the presence or absence of a test sample in a supply device and/or the type of a test sample). The method is characterized in that: supplying a sample possibly containing a substance to be analyzed to a reaction system by a supply device including a light-transmitting region made of a light-transmitting material; reacting the reagent for detecting an analyte with the sample to be detected in the reaction system; in the method for analyzing the analyte for analyzing a signal from a reaction product thereof, in the supplying step, the light is irradiated to the light-transmitting region of the supplying device, and the optical intensity is analyzed.

According to a preferred embodiment of the discrimination method of the present invention, the supply device is a dispensing device to which a tip (preferably, a tip that can be detachably attached) can be attached, and which can suck and discharge a liquid by the tip. That is, the present invention relates to a method for determining the type of a test sample (preferably, whether or not a test sample is present in a tip, and/or the type of a test sample, more preferably, whether or not a tip is attached, whether or not a test sample is present in a tip, and/or the type of a test sample), comprising: in the method for analyzing an analyte, which comprises supplying a sample possibly containing an analyte to a reaction system (preferably, dispensing the sample) by a dispensing apparatus having a tip attached thereto and capable of aspirating and dispensing a liquid through the tip, reacting the analyte detection reagent with the sample, and analyzing a signal derived from a reaction product of the reaction, in the supplying step (i.e., a state in which the sample is aspirated by the tip), a sample holding portion of the tip is irradiated with light, and the optical intensity thereof is analyzed.

According to another preferred embodiment of the determination method of the present invention, the supply device is a tube or a transfer channel. That is, the present invention relates to a method for determining the type of a test sample (preferably, whether or not a test sample is present in a supply device, and/or the type of a test sample). The method is characterized in that: in the method for analyzing an analyte, which comprises supplying a sample possibly containing an analyte to a reaction system through a tube or a transport channel including a light-transmitting region made of a light-transmitting material, reacting the analyte detection reagent with the sample, and analyzing a signal from a reaction product of the reaction, the light-transmitting region is irradiated with light in the supplying step (i.e., in a state where the sample passes through the tube or the transport channel), and the optical intensity of the light-transmitting region is analyzed.

According to still another preferred embodiment of the present invention, the test sample is whole blood, serum or plasma.

The present invention also relates to the analyzer, wherein a sample possibly containing a substance to be analyzed is supplied to a reaction system by a supply device, and the reaction system is configured to react the sample with a reagent for detecting the substance to be analyzed, and to analyze a signal from a reaction product of the reagent, the analyzer comprising:

(a) a supply device including a light-transmitting region made of a light-transmitting material;

(b) a light irradiation device capable of irradiating light to the light transmission region of the supply device in the supply step;

(c) an optical analysis device capable of analyzing an optical change of light irradiated to the light transmission region; and

(d) and a discrimination device for discriminating the type of the test sample based on the optical intensity.

The above-mentioned discriminating means may include, for example:

boundary value memory means derived from the previously measured values;

a comparison means for comparing the measured value with the stored boundary value;

indicating means for indicating a subsequent reaction route (or warning) based on the result of the comparison, and

and a comparison result output device (warning device).

According to a preferred embodiment of the analyzer of the present invention, the supply device may be a dispensing device to which a tip (preferably, detachably attached) is attached, and which is capable of sucking and discharging a liquid via the tip. That is, the analyzing apparatus according to the present invention has the following features: an analyzer for analyzing a substance to be analyzed, which supplies a sample possibly containing the substance to be analyzed to a reaction system (preferably, to be separated) by a dispensing device equipped with a tip and capable of sucking and discharging a liquid by the tip, reacts the sample with a reagent for detecting the substance to be analyzed, and analyzes a signal from a reaction product of the reaction with the reagent, comprising:

(a) a dispensing device to which a tip can be attached and which sucks and discharges a liquid through the tip;

(b) a light irradiation device capable of irradiating light to a sample holding portion of the tip in the supply step (i.e., a state where the sample to be tested is sucked into the tip);

(c) an optical analysis device capable of analyzing an optical change of light irradiated to a sample holding portion of the tip; and

(d) and a determination device for determining the type of the test sample (preferably, whether or not the test sample is present in the tip, and/or the type of the test sample, more preferably, whether or not the tip is attached, whether or not the test sample is present in the tip, and/or the type of the test sample) based on the optical intensity.

According to another preferred embodiment of the analytical device of the present invention, the supply means may be a tube or a transfer channel. That is, the analyzing apparatus according to the present invention has the following features: an analyzer for analyzing a substance to be analyzed by supplying a sample possibly containing the substance to be analyzed to a reaction system through a tube or a transport channel including a light-transmitting region made of a light-transmitting material, reacting the reagent for detecting the substance to be analyzed with the sample in the reaction system, and analyzing a signal from a reaction product of the reaction, the analyzer comprising:

(a) a tube or a transport channel including a light-transmitting region made of a light-transmitting material;

(b) a light irradiation device capable of irradiating light to the light transmission region of the tube or the transport channel in the supply step;

(c) an optical analysis device capable of analyzing an optical change of light irradiated to the light transmission region; and

(d) and a determination device for determining the type of the test sample (preferably, whether or not the test sample is present in the tube or the transport channel, and/or the type of the test sample) based on the optical intensity.

According to another preferred embodiment of the analytical device of the present invention, the test sample is whole blood, serum or plasma.

Effects of the invention

According to the present invention, in order to automatically discriminate the type of the test sample, the operator can omit the operation of inputting the type of the test sample to the analyzer in advance or setting the type of the test sample. For example, a private doctor who does not have a special device such as a centrifuge or the like, or is particularly useful for emergency examination with insufficient time. In addition, not only the type of the test sample can be discriminated, but also, for example, it can be checked that the test sample has been forgotten to be loaded. Further, in an automatic analyzer equipped with a dispensing tip, it is also possible to simultaneously check the condition of a missing dispensing tip.

Drawings

FIG. 1 is a front view (A) and a side view (B) schematically showing one embodiment of an automatic analyzer to which the discrimination method of the present invention can be applied.

FIG. 2 is an explanatory view schematically showing an implementation procedure of an embodiment of an automatic analyzer to which the discrimination method of the present invention can be applied.

FIG. 3 is an explanatory view schematically showing one embodiment of an optical analysis system applicable to the present invention.

Fig. 4 is a partially enlarged front view (a) and a partially enlarged side view (B) schematically showing a state in which one embodiment of an optical analysis system applicable to the present invention is incorporated in an automatic analyzer.

Description of the symbols

An automatic analysis device; a detection table; a cartridge;

a suction head; a nozzle;

a light emitting diode; a photodiode;

an operational amplifier for current-voltage conversion; an AD converter.

Detailed Description

The discrimination method of the present invention can be applied to any method including a step of supplying a test sample to a reaction system in an automatic analysis method of a test sample (for example, a biological body fluid, particularly, blood). For example, the present invention can be applied to an automatic analysis method including a step of supplying (for example, sorting) a test sample to a reaction system by a dispensing device capable of mounting a tip and sucking and discharging a liquid through the tip, or an automatic analysis method including a step of supplying a test sample to a reaction system by a transport device (for example, a tube or a transport channel) capable of sucking a test sample from one end and discharging a test sample from the other end. The analyzer of the present invention can be applied to any automatic analyzer provided with a supply device for supplying a sample to a reaction system. For example, the present invention can be applied to a device equipped with a dispensing device capable of mounting a tip to which a liquid can be aspirated and discharged, or a device equipped with a transport device (e.g., a tube or a transport channel) capable of aspirating a test sample from one end and discharging the test sample from the other end.

An example of an automatic analysis method and apparatus to which the discrimination method of the present invention can be applied will be described with reference to fig. 1 and 2.

An automatic analyzer 1 shown in fig. 1 is equipped with a test table 2 on which a cartridge 3 having a large number of wells into which a test sample and/or a reagent for detection can be dispensed is arranged, and a plurality of nozzles 5 on which a tip 4 can be attached and through which a liquid can be sucked and discharged are arranged in a row above the test table. The nozzle 5 can be moved up and down in the vertical direction, and when the lower end of the tip 4 is lowered to the bottom, the solution in the well of the cartridge 3 can be sucked and discharged to the well, and the solution can be stirred by continuously sucking and discharging the solution. Further, by moving the detection table 2 in the horizontal direction, a predetermined well can be disposed directly below the nozzle. Although not shown in FIG. 1, a magnet that can contact the outer side wall of the tip 4 may be disposed as necessary, and in this case, B/F separation can be performed in the tip by using the magnetic particles as a detection reagent (for example, magnetic particles having an antibody specific to a compound to be analyzed coated on the surface).

In the present invention, as a supply device for supplying a sample to be tested to a reaction system, in addition to a nozzle to which a tip can be attached as shown in FIG. 1, there may be used, for example, a suction/discharge device in which a tip portion and a nozzle portion are integrated, or a transport device capable of sucking a sample from one end portion and discharging a sample from the other end portion. Examples of the transport device include a tube (e.g., a hose or a capillary tube), a transport channel, and the like. The present invention will be described below by taking as an example a configuration in which a dispensing apparatus capable of attaching a tip and sucking and discharging a liquid by the tip is used as a supply apparatus, but the present invention is not limited thereto.

Fig. 2 shows an example of an automatic analysis method using the automatic analysis device shown in fig. 1. The automated analysis method shown in FIG. 2 is a scheme in which magnetic particles coated with the 1 st antibody, an enzyme-labeled 2 nd antibody and a luminescent substrate are used as reagents for detection, and B/F separation is performed in a tip by using a magnet that can contact the outer wall of the tip.

In the 1 st step [ (a) 1 st reaction ], a predetermined amount of a test sample is added to the 1 st well into which a predetermined amount of antibody-coated magnetic particles have been previously dispensed via a tip, and the sample is repeatedly aspirated and discharged to be sufficiently mixed with the antibody-coated magnetic particles, followed by culturing. When the antigen-antibody reaction is sufficiently performed, the reaction solution is sucked into the tip, and the reaction solution is discharged in a state where the magnetic particles are captured by the magnet on the inner wall of the tip.

In the 2 nd step [ (b) washing ], a tip is inserted into the 2 nd well into which a predetermined amount of washing solution has been previously dispensed, and the magnetic particles trapped by the magnet are washed by repeating suction and discharge of the washing solution.

In the 3 rd step [ (c) 2 nd reaction ], a tip is inserted into the 3 rd well into which a predetermined amount of an enzyme-labeled antibody solution has been previously dispensed, and the labeled antibody solution is repeatedly aspirated and discharged, followed by sufficient mixing and then culturing. When the antigen-antibody reaction is sufficiently performed, the reaction solution is sucked into the tip, and the reaction solution is discharged in a state where the magnetic particles are captured by the magnet on the inner wall of the tip.

In the 4 th step [ (d) washing ], a tip is inserted into the 4 th well into which a predetermined amount of washing solution has been dispensed in advance, and the magnetic particles trapped by the magnet are washed by repeating aspiration and ejection of the washing solution.

In the 5 th step [ (e) luminescence reaction ], a tip is inserted into the 5 th well into which a predetermined amount of a luminescent substrate solution has been previously dispensed, and the substrate solution is repeatedly aspirated and discharged to perform the luminescence reaction. After the reaction is allowed to proceed for a predetermined time, the amount or concentration of the analyte can be measured by measuring the luminescence amount.

Examples of the test sample used in the present invention include a liquid derived from a living body, particularly blood, such as whole blood, serum, or plasma.

The analyte substance contained in the test sample is not particularly limited as long as it is a substance that specifically binds to the analyte substance to form a reaction product. For example, as a combination of a substance to be analyzed and a substance specifically binding thereto, there can be mentioned, for example, an antigen and an antibody, an antibody and an antigen, a protein and a ligand, a sugar chain and a lectin, etc., and particularly preferred are an antigen and an antibody or an antibody and an antigen. Therefore, in the present specification, the term "specific binding" means biochemical specific binding to form a reaction product. Specific examples of the analyte include hepatitis B virus surface antigen (HBsAg), Hepatitis C Virus (HCV) antibody and antigen, Human Immunodeficiency Virus (HIV) antibody, human T-cell leukemia virus-1 (HTLV-1) antibody, and Treponema Pallidum (TP) antibody. Further, various myocardial markers [ Creatine Kinase MB (CKMB), myoglobin, troponin ], various hormones, serum proteins, and the like can be mentioned.

The reaction system for measuring the test substance is not particularly limited. For example, an immunological assay method using an antigen-antibody reaction is preferably used.

In the present invention, optical technology is used as the determination means. That is, in a state where a sample to be tested is sucked into the tip, light is irradiated to the sample holding portion of the tip, and the optical intensity is analyzed, whereby whether or not the tip is attached, whether or not the sample to be tested is present in the tip, and/or the type of the sample to be tested can be determined.

More specifically, it is preferable that the tip for sucking the test sample is irradiated with light at a site for holding the test sample before and after the suction, and a change in optical characteristics (e.g., transmission, reflection, scattering, etc.) is detected by a well-known device such as a light receiver, so that whether or not the tip is attached, whether or not the test sample is present in the tip, and/or the type of the test sample can be determined.

When a tube or a transport channel including a light-transmitting region made of a light-transmitting material is used as the supply device, the light-transmitting region is irradiated with light, and the presence or absence of the test sample and/or the type of the test sample can be discriminated by analyzing the optical intensity that changes according to the presence or absence of the test sample and/or the type of the test sample transported in the tube or the transport channel.

For example, as shown in specific data shown in example 1-2 described later, in a state where a tip is not attached (hereinafter, referred to as a tip non-attached state) and a state where a tip is attached (however, a state where a sample is not sucked into a tip, hereinafter, referred to as a tip attached state), the tip non-attached state is larger in light transmission amount than the tip attached state, and whether or not a tip is attached can be determined based on the light transmission amount.

In addition, since the whole blood is hardly transmitted in a state where the tip is sucked (hereinafter, referred to as a whole blood sucking state), the amount of transmitted light is smaller than that in a state where the tip is attached. On the other hand, in a state where plasma or serum is sucked into the tip (hereinafter referred to as a plasma or serum suction state), the amount of transmitted light is larger than that in a tip-mounted state but is not larger than that in a tip-unmounted state due to a lens effect of the tip.

These states are arranged from the most to the least in the amount of light transmission, and are: the non-mounted state of the tip > the state of sucking plasma or serum > the mounted state of the tip > the state of sucking whole blood, and the amount of transmitted light is used as an index to determine whether the tip is mounted, whether the sample to be tested is present in the tip, and/or the type of the sample to be tested. When the suction head is not installed, abnormal conditions such as forgetting to install the suction head, error in installation of the suction head and the like can be detected. In the tip mounting state, it is possible to detect an abnormal situation such as forgetting to place the test sample or missing. Further, the threshold value of each state cannot be generally specified depending on various conditions such as the type of the optical analysis system used, the characteristics of the tip (such as material, shape of the tip, size of the tip, etc.), etc., but it is easy for a person of ordinary skill to determine the threshold value by previously measuring the amount of light transmitted in each state through experiments in advance, for example, according to the procedure of example 1-2 to be described later.

The following shows an example of specific discrimination logic for 3 steps in the case where the test sample is (1) whole blood, (2) plasma or serum, or (3) abnormal (e.g., forgetting to set the test sample). First, in a preliminary test, the amount of light transmitted in a state of being sucked into a tip (that is, the amount of light transmitted in a state of whole blood being sucked, and the amount of light transmitted in a state of plasma or serum being sucked) is measured using a plurality of whole blood and plasma and/or serum. Further, the amount of light transmission (hereinafter referred To as light transmission To) in the tip-attached state (i.e., the state in which the sample is not sucked into the tip) is also measured. Since the amount of transmitted light is as described above, it becomes

Since the order of the state of plasma or serum aspiration > the state of tip attachment > the state of whole blood aspiration, a threshold value between the state of plasma or serum aspiration and the state of tip attachment [ hereinafter referred to as threshold value a ] and a threshold value between the state of tip attachment and the state of whole blood aspiration [ hereinafter referred to as threshold value b ] are determined in advance based on these measurement values.

Next, in order to discriminate the unknown sample, the suction head is illuminated with light, and the amount of transmitted light (hereinafter referred to as the amount of transmitted light T) is measured. When the light transmission amount T of the unknown sample is larger than the threshold value a, the state is a plasma or serum aspirated state, that is, it can be determined that the unknown sample is plasma or serum. When the light transmission amount T of the unknown sample is smaller than the threshold value b, the whole blood is aspirated, that is, the unknown sample can be determined to be whole blood. When the transmission light amount T of the unknown sample is a value between the threshold value a and the threshold value b, it can be determined that there is an abnormality.

That is, the discrimination logic (hereinafter, sometimes referred to as a one-step method) used in the present invention includes, for example, the following steps:

(A) a step of comparing an optical intensity (e.g., the amount of transmitted light) measured in a supplying step [ e.g., a state where a sample to be discriminated is sucked into a supplying device (e.g., a tip) ] with a predetermined threshold value a (i.e., a threshold value between an optical intensity in a state where plasma or serum is sucked into the supplying device and an optical intensity in a state where no sample is sucked into the supplying device) and a threshold value b (i.e., a threshold value between an optical intensity in a state where no sample is sucked into the supplying device and an optical intensity in a state where whole blood is sucked into the supplying device), and

(B) and a step of judging that the sample is plasma or serum when the optical intensity of the sample to be judged is greater than the threshold value a, judging that the sample is whole blood when the optical intensity is smaller than the threshold value b, and judging that the sample is not taken in (for example, an abnormality is present) in the supply device when the optical intensity is between the threshold value a and the threshold value b.

As shown in the specific data shown in example 2 to be described later, even if the test sample is a hemolysis test sample or a normal chyle test sample (i.e., a milky test sample having a high lipid content), the present invention can clearly distinguish between blood plasma or serum and whole blood. Further, when chylomicron plasma or serum is used as a test sample, if the amount of the contained lipid is significantly high, it may be difficult to distinguish the sample from whole blood. For example, when a chyle test sample having a significantly high lipid content is used, the light transmittance may be a value between the threshold value a and the threshold value b (i.e., an abnormality) or a value smaller than the threshold value b (i.e., a discrimination as whole blood) in the above discrimination logic. In the present invention, when a sample to be tested for chylomicron having a significantly high lipid content is mixed (or when mixing is possible), chylomicron plasma or serum can be discriminated from whole blood by diluting the sample (for example, 1.2-to 10-fold, preferably 1.5-to 5-fold, and particularly preferably 2-fold), and then measuring the light transmittance again. That is, since there is almost no change before and after dilution of whole blood and the light transmittance of chylomicron plasma or serum increases, chylomicron plasma or serum can be discriminated from whole blood.

For example, in the above discrimination logic, when the light transmission amount T of the unknown sample (raw liquid) is smaller than the threshold b (the sample is normally determined as whole blood), the unknown sample is diluted and the light transmission amount (hereinafter referred to as light transmission amount T') is measured again under the same conditions. When the unknown sample is chylomicron plasma or serum, the amount of light transmittance after dilution increases, whereas when the unknown sample is whole blood, the amount of light transmittance after dilution hardly changes. Therefore, since the threshold value c is determined in advance for the difference (T '-T) between the light transmittance (T') after dilution and the light transmittance (T) before dilution (stock solution), when "T '-T" is larger than the threshold value c, it can be judged that the unknown sample is chylomicron plasma or serum, and when "T' -T" is equal to or smaller than the threshold value c, it can be judged that the unknown sample is whole blood.

Similarly, in the above-described discrimination logic, when the light transmission amount T of the unknown sample (stock solution) is a value between the threshold value a and the threshold value b (normally, in a state where the sample is judged not to be sucked into the tip), the unknown sample is diluted, and then the light transmission amount T' is measured again under the same conditions. When the unknown sample is chylomicron plasma or serum, the amount of light transmittance after dilution increases, but the amount of light transmittance after dilution hardly changes in a state where the unknown sample is not sucked into the tip. Therefore, since the threshold value d is predetermined for the difference (T '-T) between the light transmittance (T') after dilution and the light transmittance (T) before dilution (stock solution), it can be judged that the unknown sample is chylomicron or serum when "T '-T" is larger than the threshold value d, and it can be judged that the sample is not sucked into the tip when "T' -T" is equal to or smaller than the threshold value d.

That is, the discrimination logic (hereinafter, sometimes referred to as a two-step method) used in the present invention includes, for example, the following steps:

(A) a step of comparing an optical intensity (e.g., a light transmission amount) T measured in a supplying step [ e.g., a state where a sample to be discriminated is sucked into a supplying device (e.g., a tip) ] with a predetermined threshold value a (i.e., a threshold value between an optical intensity in a state where blood plasma or serum is sucked into the supplying device and an optical intensity in a state where the sample is not sucked into the supplying device) and a threshold value b (i.e., a threshold value between an optical intensity in a state where the sample is not sucked into the supplying device and an optical intensity in a state where whole blood is sucked into the supplying device),

(B') judging whether the sample is plasma or serum when the optical intensity of the sample to be judged is larger than the threshold value a, selecting to perform the following step (C) when the optical intensity is smaller than the threshold value B, and selecting to perform the following step (D) when the optical intensity is between the threshold value a and the threshold value B,

(C) diluting a sample to be discriminated, comparing a difference (T '-T) between an optical intensity T' measured under the same conditions and the optical intensity T with a predetermined threshold c (i.e., a threshold between "T '-T" when the sample is chylomicron plasma or serum and "T' -T" when the sample is whole blood), determining that the sample is chylomicron plasma or serum when "T '-T" is larger than the threshold c, determining that the sample is whole blood when "T' -T" is not more than the threshold c, and

(D) and a step of diluting the sample to be determined, comparing the difference (T '-T) between the optical intensity T' and the optical intensity T measured under the same conditions with a predetermined threshold value d (i.e., a threshold value between "T '-T" when the sample is chylomicron plasma or serum and "T' -T" when the sample is not drawn into the supply device), determining that the sample is chylomicron plasma or serum when the "T '-T" is greater than the threshold value d, and determining that the sample is not drawn into the supply device (for example, there is an abnormality) when the "T' -T" is equal to or less than the threshold value d.

The decision logic for the two-step process is shown in Table 1.

[ Table 1]

In the present invention, the above-described one-step method or two-step method can be appropriately selected and implemented depending on the state of the test sample group (sample group) to be discriminated. For example, when the test sample group does not contain a chyle test sample having a significantly high lipid content, it is preferable to use a one-step method. Whether or not a sample of chyle is present can be determined visually, for example. Since the determination step is one step in the one-step method, analysis can be performed easily and quickly. On the other hand, when a sample to be tested contains a chylomicron sample having a significantly high lipid content in the test sample group or when the sample may contain the chylomicron sample, it is preferable to use a two-step method. The two-step method can be analyzed more accurately without visual discrimination. The results obtained by examining the influence of chyle (the amount of fat contained in the sample to be tested) with intrafat (20%, martian pharmaceuticals industry) demonstrate that the type of the sample to be tested can be determined sufficiently up to 300mg/dL by the one-step method of the present invention. The type of the sample to be tested can be distinguished by a two-step method (2-fold dilution) from the sample to be tested with a concentration of more than 300mg/dL to 1500mg/dL, particularly from whole blood.

Fig. 3 and 4 show one embodiment of an optical analysis system (light transmission system) that can be used in the present invention.

As shown in fig. 3, a Light Emitting Diode (LED)11 and a Photodiode (PD)12 are disposed to face each other with the tip 4 interposed therebetween. As the above-mentioned tip, for example, a material which is light-transmitting can be selected, and glass or a light-transmitting plastic such as polyethylene, polystyrene, polycarbonate, polyacrylic acid, or polypropylene can be used. The optical system can be optimized by means of the luminous intensity and the optical path of the light source according to the inner diameter, the wall thickness, the material and the like of the sucker. In the case of a tip made of a polypropylene material, the irradiation site is preferably 2 to 10mm in outer diameter, more preferably 3 to 6mm, 1 to 8mm in inner diameter, more preferably 2 to 4mm, and 0.2 to 2mm in wall thickness, more preferably 0.5 to 1 mm. The present invention is not limited to these values.

The wavelength of the light emitting diode may be at least a wavelength that can optically distinguish between a tip-unmounted state, a plasma or serum aspirated state, a tip-mounted state, and a whole blood aspirated state. In the case of a light emitting diode, the wavelength of light emitted therefrom is currently various, and may be selected from ultraviolet, visible, and infrared. For example, a visible region of 380-780nm can be suitably used. A more specific example is one in which 400-700nm is preferably used, and 470-635nm is more preferably used. The present invention is not limited to this wavelength range.

The irradiation angle of the light is preferably a right angle irradiation of the tip. However, if the irradiation angle is not a right angle, it is also applicable to a device for compensating the refractive index generated when light passes through the tip or the sample to be measured.

As a method for detecting transmitted light, a known technique can be applied, and the method can be appropriately modified. For example, light output from a light source (light emitting diode) 11 is passed through a tip, the amount of light (current value) detected by a light receiver (photodiode) 12 is subjected to current-voltage conversion by an operational amplifier 13, and an analog quantity is digitized by an AD converter 14 and processed by software.

In this case, the numerical value level of the type of sample to be measured and the presence or absence of the tip may be set as a threshold value in advance.

In the present invention, in addition to the light transmission system as shown in fig. 3 and 4, an image processing system using a CCD camera, for example, can be applied as an optical analysis system.

For example, in an image processing method using a CCD camera, when received light passes through RGB primary color filters, the received light can be read as color information, and a sample to be measured can be discriminated according to color. When the RGB primary color filter is not provided, whether light transmits or not can be judged through the shade of black and white.

Examples

The present invention will be specifically described below with reference to examples. The scope of the invention is not limited thereto.

Example 1: discrimination of Whole blood and plasma according to different wavelengths

In this example, the light transmission analysis system shown in fig. 3 and 4 was used to discriminate between whole blood and plasma.

3 types of light emitting diodes, i.e., a light emitting diode (GL3HD 44; スタンレ -) having a peak wavelength of 635nm, a light emitting diode (NSPY800 AS; NICIA) having a peak wavelength of 573nm, and a light emitting diode (NSPB 500S; NICIA) having a peak wavelength of 470nm were used as light source light emitting diodes. In addition, a photodiode (S6775; Hamamatsu ホトニクス) having a sensitivity wavelength range of 320-1100nm was used as the Photodiode (PD).

The tip was made of polypropylene, and the light-irradiated portion was a portion having an outer diameter of 3.6mm, an inner diameter of 2.2mm, and a wall thickness of 0.7 mm.

Water (purified water), plasma, and whole blood were used as the sample to be aspirated into the tip. With the above system, the amount of light transmission was measured for the cases where no tip was attached, only the tip was attached, and the sample was sucked into the tip. The results are shown in Table 2. The unit of table 2 is the output voltage (V).

As shown in Table 2, the amount of light detection was the largest in the state where no tip was attached (control), and the amount of light detection was reduced due to the attachment of the tip. In contrast to the decrease in the light detection amount in the state where the tip sucks whole blood, the light detection amount increases due to the lens effect of the tip in the state where water or plasma is sucked into the tip, compared to the case where the tip is used alone.

From these results, it can be seen that the whole blood and the plasma can be discriminated by measuring the amount of light detected. Further, there is a sufficient difference in the values of only the tip and the tip + plasma, and it is possible to automatically determine whether the tip is not attached, only the tip, the plasma, and the whole blood. The same results were obtained for serum.

[ Table 2]

Example 2: discrimination of various samples

This example was carried out in the same manner as example 1 except that a light-emitting diode (EFY 3863; スタンレ -) having a peak wavelength of 590nm was used as the light-emitting diode for the light source.

As the sample, plasma, whole blood obtained by adding a commercially available interfering substance (interferential dicka +; シスメックス Co.) to plasma, and water were used. The kinds and final concentrations (or turbidity) of each interfering substance were as follows. The unit "degree" represents ホルマジン turbidity.

Bilirubin (concentration 25mg/dL, 50mg/dL, 75mg/dL)

Hemoglobin (500 mg/dL, 750mg/dL, 1000mg/dL, 1500mg/dL)

Chyle (ホルマジン turbidity) (concentration 1500 degrees, 3000 degrees, 4500 degrees)

The amount of light transmitted was measured in the same manner as in example 1 for the state where the tip was not attached, only the tip, and the sample sucked into the tip. The average values of the results of 18 measurements for each sample are shown in table 3. The unit of table 3 is the output voltage (V).

As shown in Table 3, the amount of light detection was the largest in the state where the tip was not attached, and the amount of light detection was the smallest in the state where whole blood was aspirated into the tip. In a state where a liquid (plasma, bilirubin-added plasma, hemoglobin-added plasma, chylomicron plasma, or water) is sucked into the tip, the light detection amount shows a value between the control and the whole blood. From these results, it is clear that the whole blood and the plasma can be distinguished from each other by measuring the amount of light detected, and that the plasma can be clearly distinguished from the whole blood even when the plasma is colored by hemolysis or the like or is turbid in high-fat plasma.

[ Table 3]

Example 3: discrimination between chyle test sample and Whole blood

The following procedure was carried out in the same manner as in example 2.

Intrafat (20%, martian drug industry) was used as a sample, and various samples and whole blood prepared to the concentrations (lipids) shown in table 4 were used.

The amount of light transmitted was measured for each of the samples aspirated into the tip and diluted 2-fold in the same manner as in example 1. The average of the results obtained after 18 measurements for each sample is shown in Table 4. The unit of table 4 is the output voltage (V).

As shown in Table 4, it was found that the sample having a large influence of chyle (300mg/dL or more) and possibly causing erroneous recognition of whole blood could be clearly distinguished from whole blood by the two-step method.

[ Table 4]

Industrial applicability

The present invention can be applied to the use of automatically analyzing a test sample such as a biological fluid.

The present invention has been described in terms of specific embodiments, but variations and modifications apparent to those of ordinary skill are also included within the scope of the present invention.

Claims (8)

1. A method of discriminating a type of a sample to be analyzed, characterized in that a sample to be analyzed which may contain a substance to be analyzed is supplied to a reaction system by a supply device including a light-transmitting region made of a light-transmitting material, a reagent for detecting the substance to be analyzed is reacted with the sample in the reaction system, and a signal from a reaction product of the reaction system is analyzed, wherein in the supply step, the light-transmitting region in the supply device is irradiated with light, and an optical intensity of the light-transmitting region is analyzed.

2. The method according to claim 1, wherein the supply device is a dispensing device to which a tip can be attached and which can suck and discharge a liquid by the tip.

3. The method according to claim 1, wherein the supply device is a tube or a transfer channel.

4. The method according to any one of claims 1 to 3, wherein the test sample is whole blood, serum or plasma.

5. An analyzer for supplying a sample possibly containing a substance to be analyzed to a reaction system by a supply device, reacting a reagent for detecting the substance to be analyzed with the sample in the reaction system, and analyzing a signal from a reaction product of the reaction, the analyzer comprising:

(a) a supply device including a light-transmitting region made of a light-transmitting material;

(b) a light irradiation device capable of irradiating the light transmission region of the supply device in the supply step;

(c) an optical analysis device capable of analyzing an optical change of the light irradiated to the light transmission region; and

(d) and a discrimination device for discriminating the type of the test sample based on the optical intensity.

6. The analyzer according to claim 5, wherein said feeder is a dispenser to which a tip can be attached and which can suck and discharge a liquid through said tip.

7. The device of claim 5, wherein the supply device is a tube or a delivery channel.

8. The analysis device according to any one of claims 5 to 7, wherein the test sample is whole blood, serum, or plasma.