JP2007185478A - Blood component measuring device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a blood component measuring device comprising a disposable unified lancet type sensor which can easily collect blood and has little danger of accident. <P>SOLUTION: In the bowl shaped blood component measuring device, an attachable/detachable sensor part is mounted on the lancet side of a measuring device body equipped with a lancet for collecting blood by puncturing the skin of a subject by a puncturing needle, electrodes for sensor are arranged inside the sensor part, and a hole for passing the puncturing needle for collecting blood is provided on the bottom. In this blood component measuring device, the sensor part is preferably a puncturing needle attached sensor part, and the electrodes for sensor, the puncturing needle, a puncturing needle support tool and an elastic body are arranged inside the puncturing needle attached sensor part. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a blood component measuring instrument. More specifically, the present invention relates to a blood component measuring instrument including a lancet-integrated sensor that can easily collect blood and analyze blood components.

  Examples of the conventional blood component measuring device include a puncture needle, a lancet for inserting the puncture needle, a disposable blood glucose measurement chip, and a simple blood glucose meter constituted by a measurement device main body. When this blood component measuring device is used, either an electrochemical measuring method using an electrode or a colorimetric method using a test paper is used. Due to this difference in measurement method, there are two types of measuring instruments, one with an electrochemical measuring circuit and one with a colorimetric measuring circuit. Similarly, a disposable blood glucose measuring chip has a blood suction hole and a reagent-immobilized electrode. There are two types, one with blood suction holes and one with reagent-immobilized test paper.

  As described above, the conventional blood component measuring instrument is composed of four members including the puncture needle, the lancet for inserting the puncture needle, the disposable blood glucose measurement chip, and the measurement instrument main body, and its operation is complicated. . For example, after inserting the puncture needle into the lancet, bleeding from the skin, removing it from the lancet, discarding it, attaching a disposable blood glucose measuring tip to the measuring instrument body, sucking blood, measuring, and measuring blood glucose It is necessary to remove the chip from the measuring instrument body and discard it. In such a complicated operation process, it is easy to cause an accident in which the bleeding part is accidentally brought into contact with clothes and the like, and another puncture must be made, or the puncture needle is accidentally stuck into the skin. It is an accident that is likely to occur particularly in patients with retinal diseases, neurological diseases and the like with advanced diabetes, and a solution is desired.

  An object of the present invention is to provide a blood component measuring instrument comprising a disposable lancet-integrated sensor that can easily collect blood and has a low risk of an accident.

  An object of the present invention is to attach a detachable sensor unit on the lancet side of a measuring instrument body provided with a lancet for collecting blood by piercing the skin of a subject with a puncture needle, and the sensor unit Is achieved by a blood component measuring instrument which is a rod-shaped body in which a sensor electrode is arranged and a hole for passing a puncture needle for collecting blood is provided at the bottom. In this blood component measuring instrument, the sensor unit is preferably a puncture needle-attached sensor unit, and the puncture needle-attached sensor unit includes therein a sensor electrode, a puncture needle, a puncture needle support, and an elastic body.

  The blood component measuring instrument comprising the lancet-integrated sensor according to the present invention is a disposable type in which only the sensor part is replaced because the measuring instrument main body provided with the lancet and the rod-shaped sensor part are detachably mounted. Since the sensor part is a bowl-shaped body provided with a hole through which the puncture needle passes, the hole is pressed against a predetermined blood sampling position, and the puncture needle that has jumped out of the hole comes into contact with the other part. Blood can be collected without puncturing the skin, and blood collection is easy, and the used puncture needle is stored in the rod and does not need to be removed during operation. This has the effect of reducing the risk of accidents. In addition, since the sensor part is composed of a seamless rod-like body, it is superior in strength compared to a conventional sensor in which electrodes are formed on a flat substrate, and a sensor for bonding substrates together. Since a manufacturing process or the like is not necessary, the sensor part can be easily manufactured.

  In addition, when the sensor unit is a puncture needle-attached sensor unit, that is, the sensor unit is provided with a puncture needle, its support, and an elastic body in addition to the sensor electrode, the sensor unit and the blood suction unit including the puncture needle are integrated. As before, there is no need to operate the sensor unit and the puncture needle separately for each measurement, and when blood components are measured, bleeding operation by puncture, blood suction, and measurement by sensor can be performed in one chip and in one process. The effect is seen.

  A blood component measuring instrument comprising a lancet-integrated sensor according to the present invention is a sensor unit that can be attached to and detached from the lancet side of a measuring instrument body provided with a lancet for collecting blood by piercing the skin of a subject. The sensor part is a rod-like body in which a sensor electrode is arranged and a hole for passing a puncture needle for collecting blood is provided in the bottom part. The puncture needle set on the lancet is removed and replaced after each measurement. As such a blood component measuring device, the sensor unit is preferably a puncture needle-attached sensor unit, and the puncture needle-attached sensor unit has a sensor electrode, a puncture needle, a puncture needle support, and an elastic body disposed therein. Things are used.

  Generally, blood is collected, but fruit sap, sap, or the like may be used. The collected liquid is brought into direct contact with the sensor electrode, or is brought into contact with a sensor electrode on which at least one reagent such as an enzyme, an antibody, a receptor, a nucleic acid, or a mediator that reacts with the collected liquid is immobilized.

  Sensor electrodes are formed from carbon, nanocarbon, platinum, gold, palladium, nickel, etc. by bonding, fitting, printing, vapor deposition, sputtering, plating, etc. It can also be formed, which is a two-pole configuration of a working electrode and a counter electrode or a three-pole configuration of a working electrode, a counter electrode, and a reference electrode, and is common to two working electrodes in order to eliminate the influence of interfering substances such as ascorbic acid. A differential system composed of a single counter electrode can also be used. These electrode portions are preferably separated from each other by a distance of about 0.5 to 2 mm between the tip and the hole so as not to hinder blood suction or electrode contact of the sucked blood.

Here, when a sensor composed only of electrodes is used, neurotransmitters such as hydrogen peroxide, NADH, uric acid and dopamine, monoamine, alcohol, metal ions, 8-hydroxydeoxyguanosine, which is a gene damage marker, etc. Nucleic acids (see Patent Document 1), proteins (see Patent Document 2), lipids, carbohydrates or derivatives thereof can be detected.
JP 2001-258597 A USP 5563864

For example, the concentration of hydrogen peroxide can be measured electrochemically by measuring the current oxidized or reduced according to the electrode reaction of the following formula.
For oxidation by the _{electrode: H 2 O 2 → O 2} + 2H + + 2e -
For reduction with ^{_{electrodes: H 2 O 2 + 2H +}} + 2e - → 2H 2 O

  In addition, when a sensor composed of a reagent layer such as an enzyme is used together with an electrode, glucose, ethanol, lactic acid, pyruvic acid, cholesterol, creatinine, ketone bodies (β-hydroxybutyric acid) and the like can be detected.

Here, the reagents include enzymes, enzyme mutants, antibodies, nucleic acids, primers, peptide nucleic acids, nucleic acid probes, aptamers, microorganisms, organelles, chaperones, receptors, cell tissues, crown ethers, potassium ferricyanide, and other mediators. , Intercalating agents, coenzymes, antibody labeling substances, substrates, surfactants, lipids, albumin, Nafion, thiol and other functional group introduction reagents and at least one of covalent bond reagents are used. For example, when a DNA chip is prepared as shown in Patent Document 3, an intercalator (insertion agent) such as a nucleic acid probe or acridine orange, a metallointercalator such as a tris (phenanthroline) cobalt complex, or the like can be used.
JP-A-5-199898

  The reagent layer is formed on the electrode and / or the substrate around the electrode or on the electrode and the substrate by a method of dropping the reagent as an aqueous solution or an organic solvent solution with a dispenser or the like, or a method of printing the reagent as an organic solvent solution by a screen printing method. Formed to contact. The formed reagent layer is preferably dried after formation.

  Examples of the enzyme include enzymes such as oxidase and dehydrogenase such as glucose oxidase, lactate oxidase, cholesterol oxidase, alcohol oxidase, sarcosine oxidase, pyruvate oxidase, glucose dehydrogenase, lactate dehydrogenase, alcohol dehydrogenase, and hydroxybutyrate dehydrogenase. In addition, cholesterol esterase, creatininase, creatinase, DNA polymerase, and mutants of these enzymes are used.

As shown in Patent Documents 4 to 6, in an enzyme sensor, it is necessary to change the type of enzyme as a molecular identification element depending on the measurement target of the specimen. For example, glucose oxidase or glucose dehydrogenase is measured when glucose is measured, alcohol oxidase or alcohol dehydrogenase is measured when ethanol is measured, lactate oxidase is measured when lactate is measured, and total cholesterol is measured. In this case, a mixture of cholesterol esterase and cholesterol oxidase is used.
USP 6071391 USP 6156173 USP 6503381

For example, as shown in the following formula, when measuring glucose using a reaction catalyzed by glucose oxidase (GOD), the generated hydrogen peroxide is used as in the case of using a sensor composed only of electrodes. By measuring the oxidized or reduced current, the concentration can be measured electrochemically, thereby indirectly measuring the glucose concentration.

Glucose + oxygen → gluconolactone + H ₂ O ₂

In such a sensor, when the reaction is limited by the dissolved oxygen concentration and only a low concentration sample can be measured, an electron carrier (mediator) is used together with an enzyme for the purpose of expanding the detection range. As the mediator, potassium ferricyanide, ferrocene, ferrocene derivatives, benzoquinone, quinone derivatives, osmium complexes and the like are used. For example, when measuring glucose, either an enzyme such as glucose oxidase or glucose dehydrogenase and potassium ferricyanide are used. Ferricyan ion reduced by the enzyme is further oxidized to ferrocyan ion by the electrode as in the following formula, and glucose can be indirectly measured by measuring the current value at this time.

_{2 [Fe (CN) 6]} 4- → 2 [Fe (CN) 6] 3- + 2e -

  As a measuring method using the sensor of the present invention, a potential step chronoamperometry method, a coulometry method, a cyclic voltammetry method and the like for measuring an oxidation current or a reduction current are used. As a measurement method, a disposable (disposable) method is desirable.

  In the measurement, in addition to the electrode combination for differential measurement described above, the electrode material is carbon nanotube, and the interelectrode voltage is set to a specific voltage to avoid the influence of the measurement interfering substance and to avoid the target substance. It can be measured selectively. For example, when measuring sugar (glucose) in blood or urine, it is measured by applying voltage to the electrode. Depending on the voltage, not only hydrogen peroxide but also ascorbic acid, uric acid, acetaminophen, etc. However, by selecting a voltage (referred to here as a specific voltage) for an electrode containing carbon nanotubes, the electrode reacts with hydrogen peroxide, and a state where the electrode does not react so much with these contaminants can be set. An excellent biosensor can be formed. Such a specific voltage varies depending on the substance to be measured.

  One mode of a blood component measuring instrument comprising a lancet-integrated sensor according to the present invention will be described with reference to the drawings. FIG. 1 is a front view of a blood component measuring instrument main body with a puncture needle insertion portion, and FIG. 2 is a front view (a), a cross-sectional view (b), and a plan view of a bowl-shaped body attached to the measuring instrument main body ( c) and bottom view (d).

  The blood component measuring instrument main body 1 is provided with a lancet 3 for collecting blood by piercing the skin of a subject with a puncture needle 2, and the puncture needle is collected by collecting blood by an arbitrary driving method. As for blood, movement to the sensor unit is performed by capillary action. The measuring instrument main body is provided with a display section 4 indicating the measurement result, a sensor section mounting guide section 5 and a terminal section 6 of the measuring instrument main body. Here, the lancet refers to a known means that punctures the puncture needle into the subject's skin to collect blood, and further returns the puncture needle to its original position by a driving means such as a spring. Consists of a storing mechanism and an operating mechanism for the puncture needle. In addition, any material such as plastic, rubber, or metal can be used as the puncture needle.

  The rod-shaped body 11 attached to the measuring instrument main body 1 is formed from a biodegradable material such as polylactic acid, plastics such as polyethylene terephthalate and polycarbonate, glass, ceramics, paper, and the like, and generally the circumferential surface thereof. A sensor electrode 12 is disposed on the sensor electrode, and a reagent 13 that reacts with a collected liquid such as blood is immobilized on the sensor electrode according to the type of the measurement object, if necessary. Reference numeral 14 denotes a terminal portion of a sensor electrode that comes into contact with the terminal portion 6 of the measuring instrument main body when mounted, and is formed of a leaf spring, a contact probe, or the like. Further, a hole 15 for passing the puncture needle 2 for collecting the collected liquid is provided at the bottom of the rod-like body, and a guide groove 16 for fitting the guide portion 5 is provided on the inner peripheral surface of the rod-like body. ing. It is desirable to apply a surfactant such as lecithin around the hole 15 so that blood or the like is easily sucked. Note that the measuring instrument main body and the bowl-shaped body can be attached by other means such as screwing.

  3 to 8 show a mode in which the sensor part is a puncture needle-attached sensor part, and a sensor electrode, a puncture needle, a puncture needle support, and an elastic body are arranged inside the sensor part. By attaching the puncture needle to the sensor unit, there is an effect that the sensor unit and the puncture needle that need to be replaced for each measurement can be attached and detached simultaneously. In addition, by providing an elastic body together with the puncture needle and the puncture needle support, it is possible to smoothly puncture the subject.

  In the embodiment shown in the plan view (a), the centerline cross-sectional view (b), and the centerline vertical and cross-sectional view (c) of FIG. 3, the frame-like body 11 has a bottomed frame shape on the inner wall surface side. A puncture needle support 22 is fitted, and a rod-like elastic body 23 is passed to the upper open end side. And the puncture needle support 24 of the puncture needle 2 is supported so that it may pass through the center part of the bottom part 21 of the support body 22, and the rod-shaped elastic body 23, respectively.

  When the head of the puncture needle support 24 is hit by a lancet striker (not shown) in the main body of the measuring instrument, the puncture needle support 24 is lowered by the driving force to puncture the puncture needle 2 into the skin and collect blood. After that, the puncture needle is raised by the repulsive force of the rod-like elastic body 23. The collected blood is moved from the hole 15 serving as a blood suction port to the sensor units 14 and 14 by capillary action.

  Here, the elastic body may be plate-shaped, rod-shaped, coil-shaped, etc., and the material thereof is plastic, rubber (including thermoplastic elastomer), metal, and the like.

  In the embodiment shown in the plan view (a), the centerline cross-sectional view (b), and the centerline vertical and cross-sectional view (c) of FIG. 4, the puncture needle support is formed by the bottomed circular box-shaped support 25. The puncture needle support 24 passes through the center of the bottom 21 of the circular box-shaped support 25 fitted on the circumferential surface of the bowl-shaped body 11, and the non-penetrating portion of the puncture needle support 24 A coiled elastic body 26 (spring) is attached.

  In the embodiment shown in the plan view (a), center line cross-sectional view (b), and center line vertical and cross-sectional view (c) of FIG. 5, in the embodiment shown in FIG. A coiled elastic body 26 is attached to the portion of the puncture needle support 24 that penetrates the bottom 21.

  Measurement using a blood component measuring instrument composed of a lancet-integrated sensor configured as described above is performed by contacting the collected blood with the sensor electrode on which the reagent is immobilized, and applying a voltage from the measuring instrument main body thereto. The amount of substance to be measured can be measured by measuring the generated current value. The measuring instrument main body may have a wireless communication function for transmitting measured values to a remote medical department or an external device such as a personal computer.

It is a front view of the blood component measuring device main body with a puncture needle insertion part. FIG. 3 is a front view (a), a cross-sectional view (b), a plan view (c), and a bottom view (d) of a bowl-shaped body attached to the measuring instrument main body. FIG. 4 is a plan view (a), a centerline cross-sectional view (b), and a centerline vertical and cross-sectional view (c) of one embodiment of a puncture needle attached rod-like body. FIG. 8 is a plan view (a), a centerline cross-sectional view (b), and a centerline vertical and cross-sectional view (c) of another embodiment of the puncture needle attached rod-like body. FIG. 6 is a plan view (a), a centerline cross-sectional view (b), and a centerline vertical and horizontal cross-sectional view (c) of still another embodiment of the puncture needle attached rod-like body.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Measuring device main body 2 Puncture needle 3 Lancet 4 Display part 5 Guide part 6 Terminal part of measuring device main body 11 Rod-like body 12 Sensor electrode 13 Reagent 14 Sensor electrode terminal part 15 Hole 16 Guide groove 21 Bottom 22 Support 23 Rod-shaped elastic body 24 Puncture needle support tool 25 Circular box-shaped support body 26 Coiled elastic body

Claims (16)

  A detachable sensor part is mounted on the lancet side of a measuring instrument body provided with a lancet for collecting blood by piercing the skin of a subject, and the sensor part has a sensor electrode therein. A blood component measuring instrument characterized by being a rod-shaped body provided with a hole in the bottom for passing a puncture needle for collecting blood.   The blood component measuring instrument according to claim 1, wherein the sensor part is a puncture needle attached sensor part.   The blood component measuring instrument according to claim 2, wherein the puncture needle-attached sensor section includes a sensor electrode, a puncture needle, a puncture needle support, and an elastic body.   The blood component measuring instrument according to claim 1, 2, or 3, wherein a reagent that reacts with blood is immobilized on the sensor electrode.   The blood component measuring instrument according to claim 4, wherein the reagent that reacts with blood is at least one of an enzyme, an antibody, a receptor, a nucleic acid, and a mediator.   5. The amount of a substance to be measured can be measured by contacting the collected blood with a sensor electrode on which a reagent is immobilized, applying a voltage from the measuring instrument body, and measuring the generated current value. Or the blood component measuring device of 5.   The head of the puncture needle support provided in the rod is hit by a lancet striker in the main body of the measuring unit, the puncture needle is lowered, the puncture needle is inserted into the skin, and the collected puncture needle is raised by the elastic body. The blood component measuring device according to claim 3, which is configured as described above.   The blood component measuring instrument according to claim 7, wherein a puncture needle support body head provided in a rod-like body is attached to a lancet, and the puncture needle is lowered by its driving force.   The blood component measuring instrument according to claim 3 or 7, wherein the elastic body is plastic, rubber or metal.   The blood component measuring instrument according to claim 3, 7 or 9, wherein the elastic body is plate-shaped, rod-shaped or coil-shaped.   The blood component measuring instrument according to claim 1, wherein the measuring instrument main body is provided with a display unit for indicating a measurement result.   The sensor unit mounting guide portion is provided in the measurement unit main body, and the guide groove provided on the peripheral surface of the rod-shaped body is fitted into the guide unit, whereby the measurement unit main body and the rod-shaped body are mounted. Or the blood component measuring device of 2.   The blood component measuring device according to claim 1 or 2, wherein the measuring device main body and the rod-shaped body are attached by screwing.   The blood component measuring instrument according to claim 1 or 2, wherein the sensor electrode is disposed inside the sensor section on the peripheral surface of the rod-shaped body.   The blood component measuring device according to claim 1 or 14, wherein the sensor electrode has a two-electrode configuration of a working electrode and a counter electrode or a three-electrode configuration of a working electrode, a counter electrode, and a reference electrode. The blood component measuring instrument according to claim 15, wherein the sensor electrode is composed of two working electrodes and one common counter electrode.

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