JP2713255B2 - Leachate suction device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a leachate suction device for sucking and collecting leachate in a living body, and more particularly to a leachate suction device used for collecting a small amount of bodily fluid without blood.

[0002]

2. Description of the Related Art Conventionally, continuous measurement of a chemical substance concentration in a living body such as a glucose concentration or a blood glucose level in a living body has conventionally been performed.
Generally, blood was collected and measured with a dedicated sensor. This measuring method uses a biosensor provided with an immobilized enzyme electrode to measure the concentration, and is characterized in that even a small sample can be measured with high sensitivity if the biosensor has a small size.

[0003] Therefore, these measuring methods can be used in the fields of medicine, diagnosis and biochemistry, for example, for diagnosing diseases and health management by measuring the concentration of organic components contained in plasma, urine and the like. However, sufficient attention has to be paid to the risk of infection and bleeding as well as the pain of the patient involved in blood collection and the provision of labor on the medical side.

[0004] Recently, as a collection method for relieving the pain on the patient side and the labor on the medical side, there has been proposed a method in which the stratum corneum of the skin is locally removed, a bodily fluid is collected from the portion, and the exudate is measured for the concentration of the component with a sensor. It has been developed. An example of this method is described in NEC Technical Report Vol. 16, No. 9 (1993) 83rd
Page to page 91.

In this method, interstitial fluid sucked from the skin from which the stratum corneum has been peeled off is reacted with an immobilized enzyme membrane on an ion-sensitive field effect transistor (ISFET), and the glucose concentration is measured based on the degree of the reaction. It is. A leachate suction device has been used to collect the leachate, which is the interstitial fluid necessary for this measurement.

FIG. 7 is a cross-sectional view of a leachate suction device showing an example of the related art. The leachate collecting apparatus disclosed in Japanese Patent Application Laid-Open No. 4-341241 is referred to as a spacer fixed by a frame 13 in an opening 2 which comes into contact with the skin of a suction cell body 1 for sucking leachate as shown in FIG. A nylon mesh 14 is provided inside, and the air is evacuated from the suction port 3 to collect a leachate.

[0007]

The above-mentioned conventional exudate suction device removes the stratum corneum on the skin surface, exposes the skin surface called the dermis, and sucks the exudate to collect the exudate.

[0008] The thickness and condition of the stratum corneum cannot be specified because there are individual differences such as age, gender, living environment and body parts. Usually, it is about 10 to 30 μm in the case of the arm, and it is the uppermost tissue where the skin is metabolized.

In order to remove the stratum corneum, the adhesive tape is mechanically pressed against the skin surface, the skin surface is mechanically rubbed off, and the peeling operation is repeatedly performed. As described above, the required time varies due to individual differences and is not constant, and in some cases it may be painful.

The degree of removal of the stratum corneum influences the time for sucking and leaching the leachate, and determines the leaching efficiency. For example, the same person may need 15 minutes or 1 hour to obtain 10 μl of leachate.

Furthermore, when the stratum corneum is removed, a pretreatment for cleaning such as degreasing and hair removal is required depending on the site, and a clinical treatment for suppressing inflammation after suction and leaching is required.

Accordingly, an object of the present invention is to provide a leachate suction device which can efficiently and easily collect a body fluid extracted from a living body.

[0013]

The leachate suction device of the present invention has a suction port for sucking and reducing the pressure for infusion of leachate from the surface of a living body, and an opening on the side directly contacting the surface of the living body. A leachate suction device comprising a flow path plate fitted and fixed in the opening and directly in contact with the surface of the living body, and a vibrator installed in or outside the opening to vibrate the flow path plate; The vibrator is installed on the suction port side of a road plate, and a plurality of microneedles and through holes are formed on a surface of the flow path plate that directly contacts the living body surface.

[0014]

Next, the present invention will be described with reference to the drawings.

FIG. 1A is a sectional view showing a first embodiment of a leachate suction device according to the present invention. In this exudate suction device, a flow channel 5 is formed radially from the center on the suction port 3 side of the flow channel plate 4, and a plurality of conical fine needles 6 are formed on the opening 2 side.
Is formed in the opening 2 of the suction cell body 1. A plurality of through holes 7 are formed between the fine needles 6 and penetrate through the flow channel 5. On the other hand, on the flow path plate 4, a flow path port 8 is formed at the center, and is connected to the suction port 3. Leakage of the flow passage 8 from the suction system affects the leaching efficiency and the liquid sending efficiency of the leachate. Therefore, a seal is provided between the suction cell body 1 and the flow passage 8 of the flow passage plate 4 via an O-ring 9. ing.

Further, a flat-plate-shaped piezoelectric vibrator 10 is mounted on the flow path plate 4, and a central portion thereof is fixed. FIG.
As shown in (b), a hollow portion 12 is provided at the center of the piezoelectric vibrator 10 in order to avoid a portion corresponding to the flow path opening 8 of the flow path plate 4. Two electrodes 11 for supplying electric energy to vibrate are installed in a plane on the upper surface of the piezoelectric vibrator 10 and are wired to the connector 13 from above the suction cell.

[0017]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The leaching solution suction apparatus having such a structure has, for example, an outer diameter of a channel plate 4 of 30 mm, a thickness of 0.5 mm, a fine needle 6 length of 30 μm, a needle diameter of 20 μm, and a pitch of 0.1 m.
m, the diameter of the through-hole 7 is 50 μm, and the number of the fine needles 6 and the number of the through-holes 7 formed in the flow path plate 4 is about 80,000. When suction pressure is reduced from the suction port 3 (for example, 0.5 atm), the skin surface is depressurized through the flow path port 8, the flow channel 5, and the through-hole 7, and the flow path plate 4 is pressed against the skin surface. Further, at this time, when an AC voltage is applied to the piezoelectric vibrator 10 to apply longitudinal vibration, the flow path plate 4 that is installed in contact with the piezoelectric vibrator 10 is excited, and the fine needle 6 penetrates into the stratum corneum of the skin and penetrates the stratum corneum. Then, the tip of the fine needle 6 reaches at least the dermis where the interstitial fluid to be leached exists. Although the thickness of the stratum corneum varies among individuals, it is said to be 10 to 30 μm, and the thickness of the dermis of the lower tissue cells is several tens of μm. Since the fine needle 6 penetrates into the skin by the length of the needle, it does not reach a site where there is a capillary blood vessel, and thus does not bleed. It is desirable that the tip of the fine needle 6 is sharp, but even if the displacement amount is several μm, since the excitation is continued, the fine needle 6 is easily gradually penetrated into the skin and stops at the through hole 7. In addition, the stratum corneum is usually dried in the final form of the uppermost layer of living cells, and is deposited in a scale of about several tens of μm in diameter. The diameter and pitch of the fine needles 6 and the through-holes 7 are preferably as small as possible, but in this embodiment, a range that can be easily formed by an etching method using a photolithography technique is selected.

When suction and vibration are continued in such a state, the fine needle 6 reaches the dermis, and the interstitial fluid oozes out between the fine needle 6 and the side of the skin. Fine needle 6 due to vibration
A temporary space is created between the skin and the skin contact surface, and the exudate is easily leached.

Therefore, not only the work which conventionally requires a long time for removing the stratum corneum can be omitted, but also there is an effect that even if there is an individual difference in the stratum corneum thickness, there is no variation in the leachate leaching efficiency. For example, when measuring the diurnal variation of the glucose component concentration in the blood, the required amount of leachate is 10 μm.
If it is set to 1, it takes about 15 to 30 minutes for each individual difference, but it can be stably set to 15 minutes or less. The resolution with respect to time of the situation where the glucose concentration changes is improved, and the accuracy of clinical diagnosis is also improved.

The piezoelectric vibrator 10 for exciting vibration in the flow path plate 4 is approximately 30 mm in size equivalent to the diameter of the flow path plate 4 and is housed in the opening 2. Its shape is a circular flat plate, for example, if a ceramic sintered body such as 0.5 mm thick barium titanate or lead zirconate titanate is used,
Since a vertical vibration can be easily applied from an audible frequency to an ultrasonic wave to a megasonic, a piezoelectric vibrator having a simple structure can be obtained. It is clear from the principle that setting the operating frequency as high as 1 kHz or more is more effective because it is less susceptible to the resonance frequency of the suction cell body.

FIG. 2 is a pattern diagram of the electrodes of the piezoelectric vibrator of FIG. In this piezoelectric vibrator, as shown in FIG. 2, a plurality of electrode 11 patterns are formed independently radially. When the operation is performed so that a voltage is continuously applied between the adjacent electrodes 11, displacement occurs in a direction in which the electrodes are arranged, and it becomes possible to vibrate uniformly from near the center to near the edge of the disk. . In the structure as shown in FIG. 1, the portion showing the largest displacement is near the end of the disk because the center portion is fixed, whereas all the fine needles 6 of the flow path plate 4 vibrate with the same amplitude. There is a feature that can be done. Therefore,
A small amount of leachate can be collected from the entire area of the flow path plate, which has the effect of further improving the collection efficiency.

FIG. 3 is a sectional view showing a second embodiment of the leachate suction device of the present invention. As shown in FIG. 3, this leachate suction device is installed so as to fit an annular piezoelectric vibrator 20 in the opening 2 of the suction cell body 1, The plate 4 is fixed.

The leachate suction device having such a structure gives horizontal vibration to the flow path plate 4. That is, for example, the annular piezoelectric vibrator 20 has a thickness of 2 mm, an inner diameter of 26 mm, and an outer diameter of 3 mm.
0 mm, electrodes are installed on the inner wall and the outer wall side,
An AC voltage is applied to this part. The piezoelectric vibrator 20 not only provides vibration that pushes and pulls the flow path plate 4 with respect to the central axis, but also serves as a source of action that moves the flow path plate 4 up and down. In addition, an effect of extending and contracting the skin surface itself also occurs. At this time, the fine needles 6 of the flow path plate 4 do not necessarily have to be sharp in the vertical direction.
Even in the case of an arrow-shaped projection in which a thick film having a thickness of about 30 μm, which is sharp in the horizontal direction, is patterned, the stratum corneum can be penetrated.

Therefore, in addition to the effect shown in the first embodiment, the effect of extending the skin surface and the vibration of the flow channel plate 4 in the horizontal direction allow the fine needle 6 and the stratum corneum to intersect. The space generation is expanded, and the leaching efficiency is further improved.

FIG. 4 is a sectional view showing a third embodiment of the leachate suction device of the present invention. As shown in FIG. 4, the leachate suction device is installed so that an annular piezoelectric vibrator 20 (inner diameter 2r) is fitted into the opening 2 of the suction cell body 1. An annular extrusion portion 21 (outer diameter 2r) is fixedly provided on the inner surface. The inner surface side of the push-out portion 21 has a taper angle (α) 25 as shown in the figure, and has a structure in contact with the flow path plate 4 provided with a similar taper angle on the outer periphery. In the third embodiment, an annular piezoelectric vibrator 2 having an inner diameter 2r is used.
0 excites the inner diameter to its maximum value 2 (r + Δ
r), the vibration having the minimum value 2 (r-Δr) is repeated. Due to the radial expansion and contraction, the annular extruded portion 21 fixedly provided to the piezoelectric vibrator 20 also causes the radial expansion and contraction to move the flow path plate 4 in contact with the piezoelectric vibrator 20 through the taper angle 25. It is structured to vibrate in the Z direction. Specifically, when the radius r of the extruded portion 21 is reduced to r-Δr, the flow path plate 4 is extruded in the + Z direction (downward in the figure) via the tapered portion of the angle α, and the extruded portion is extruded. The distance (ΔZ) is ΔZ = Δr × tanα. When the radius of the push-out portion 21 increases, the flow path plate 4 is pushed back in the −Z direction by the elasticity of the skin, and as a result, the flow path plate 4 repeats the vibration (ΔZ = ± Δr × tan α) in the Z direction. It has a structure.

In the third embodiment having the taper angle (α), the displacement (Δr) of the piezoelectric vibrator 20 is increased. When the taper angle α is set to 45 degrees or more, the structure is such that the displacement amount Δr is enlarged. For example α
= 1.73 times at 60 degrees, 2.75 times at α = 70 degrees,
The magnification can be increased to 5.67 times when α = 80 degrees, and to 11.4 times when α = 85 degrees. By using the piezoelectric vibrator 20 with Δr = 0.2 μm and setting the taper angle (α) to 85 degrees, about 2
A fine needle 6 having a stroke of μm was obtained.
In order to vibrate the fine needle 6 smoothly, it is important to improve the sliding of the tapered portion, and it is necessary to smooth the tapered surface (preferably a mirror surface state) or to use a medicated oil which is usually used for obtaining a lubricating effect. It was effective to put a small amount of such as (preferably low viscosity) on the tapered surface.

By providing the function of enlarging the displacement amount described in the third embodiment to the leachate suction device, a smaller piezoelectric vibrator can be used, and the design of the leachate suction device can be reduced. It has the effect of being easy.

In the present embodiment, the disk shape is the shape of the suction cell, but the present invention is not limited to this, and the same effect can be obtained with a rectangular suction cell.

FIG. 5 is a sectional view showing a fourth embodiment of the leachate suction device of the present invention. As shown in FIG. 4, the leachate suction device has a disk-shaped piezoelectric vibrator 30 installed and fixed around the suction port 3 outside the suction cell body 1. A channel plate 4 is fitted into the opening 2 of the suction cell body 1, and the fine needle 6 and the through-hole 7 are formed on the opening 2 side of the channel plate 4 in the first embodiment. This is equivalent to the embodiment.

The leachate suction device having such a structure vibrates by applying an AC voltage to the electrodes formed on the upper and lower surfaces of the disc-shaped piezoelectric vibrator 30 installed outside the suction cell body 1. As a result, the entire suction cell body 1 is vibrated,
The fine needle 6 penetrates the stratum corneum, and the interstitial fluid can be leached from the through hole 7.

Therefore, the effect shown in the leachate suction device shown in the first embodiment can be obtained in the same manner. In addition, since the piezoelectric vibrator 30 is installed outside the suction cell body 1, assembly is easy. Since it is not necessary to provide the interior in the opening 2, the difficulty of designing and manufacturing is reduced, especially regarding the accuracy of the outer diameter.

FIG. 6 shows a fifth embodiment of the leachate suction device of the present invention.
It is sectional drawing which shows embodiment. As shown in FIG. 6, the leachate suction device has an annular piezoelectric vibrator 40 installed on the flow path plate 4 in the opening 2 of the suction cell body 1. The circumferential end of the channel plate is fitted and fixed to the side surface of the opening. For example, if the diameter of the opening 2 is 30 mm, the annular piezoelectric vibrator 40 has an inner diameter of 20 mm and an outer diameter of 25 mm. And a size selected to be smaller by the radius l and bonded to the channel plate. The electrodes to be applied to the ring-shaped piezoelectric vibrator 40 are provided on the upper and lower surfaces, and the piezoelectric vibrator 40 is set so as to generate vibration parallel to the applied electric field and perpendicular to the flow path plate 4.

The vibration amplitude of the flow path plate 4 of the leachate suction device having such a structure is, for example, 1 μm at the portion where the piezoelectric vibrator 40 is mounted, and the center portion is about four times as large as 4 μm.
The amplitude is increased to about m. That is, it has an amplitude amplification function. Although the central portion has the maximum amplitude, since the amplitude of the vertical vibration is large, the fine needle 6 easily penetrates into the stratum corneum, and conversely, there is an advantage that the microneedle 6 can be easily driven even by applying a small voltage.

Although the novelty according to the configuration of the present invention has been described with reference to the embodiments, the present invention is not limited to these. For example, flat and annular piezoelectric vibrators are used, but the same effects can be obtained by combining them, or by dividing them into two or more planes and installing them. You may use a child. Further, the inner diameter of the opening of the suction cell was set to about 30 mm, and the outer diameters of the flow path plate and the piezoelectric vibrator were determined in accordance with the dimensions, but were temporarily set in order to compare the effect with a conventional mesh. It is a dimension and can be arbitrarily selected without being limited to this.

Further, the shape of the fine needle has been described as a conical shape or an arrow shape. However, even if a fine needle having a polygonal pyramid shape, a cylindrical shape, or a combination of these shapes is used, it can easily penetrate into the stratum corneum when vibration is applied. Can be.

[0036]

As described above, according to the present invention, a plurality of fine needles are provided on a flow path plate which is fitted into the opening of a suction cell body which comes into contact with the surface of a living body and suctions a leachate. By installing a vibrator that vibrates the exudate, it is possible to obtain an effect that the exudate can be suctioned and collected only by a simple cleaning operation without removing the stratum corneum on the skin surface. Also, because it does not remove the stratum corneum,
The degree of removal of the stratum corneum has caused a large variation in the leachate collection efficiency in the past, but this has been eliminated, and there is also an effect that individual differences are reduced and stable collection efficiency is obtained.

[Brief description of the drawings]

FIG. 1 (a) is a cross-sectional view showing a first embodiment of a leachate suction device of the present invention. FIG. 2B is a plan view showing an electrode pattern of the piezoelectric vibrator shown in FIG.

FIG. 2 is a plan view showing another example of a piezoelectric vibrator electrode pattern for exciting the flow path plate of FIG.

FIG. 3 is a sectional view showing a second embodiment of the leachate suction device of the present invention.

FIG. 4 is a sectional view showing a third embodiment of the leachate suction device of the present invention.

FIG. 5 is a sectional view showing a fourth embodiment of a leachate suction device of the present invention.

FIG. 6 is a sectional view showing a fifth embodiment of the leachate suction device of the present invention.

FIG. 7 is a cross-sectional view of a conventional leachate suction device.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Suction cell body 2 Opening 3 Suction port 4 Flow path plate 5 Flow path groove 6 Fine needle 7 Penetration port 8 Flow path port 9 O-ring 10, 30 Disk-shaped piezoelectric vibrator 20, 40 Ring-shaped piezoelectric vibrator 11 Electrode 12 Hollow part 13 Frame 14 Mesh 21 Extruded part 25 Taper angle (α)

Claims (6)

(57) [Claims] 1. A suction cell body having a suction port for leaching an exudate from the surface of a living body for reducing pressure, a suction cell body having an opening on a surface side in direct contact with the surface of the living body, and the living body fixed in the opening and directly connected to the living body. In a leachate suction device including a flow path plate that contacts a surface and a vibrator installed inside or outside the opening to vibrate the flow path plate, the vibration is generated on the suction port side of the flow path plate. A leachate suction device, wherein a plurality of microneedles and through-holes are formed on a surface of the flow channel plate which directly contacts the surface of the living body, in which a child is installed. 2. The leachate suction device according to claim 1, wherein the vibrator is a piezoelectric vibrator. 3. The leachate suction device according to claim 2, wherein the piezoelectric vibrator has a plurality of voltage application electrodes radially arranged on one plane. 4. The suction device according to claim 2, wherein the piezoelectric vibrator is installed around the suction port above the suction cell body.
A leachate suction device as described. 5. The leachate suction device according to claim 1, wherein an annular vibrator is provided on an outer periphery of the flow path plate. 6. The leachate suction device according to claim 2, wherein the piezoelectric vibrator is installed inside a fulcrum of the flow path plate.