JPH0951878A - Exudation liquid sucking device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To suck and sample exudation liquid only by cleaning work by providing plural micro thin needles in a passage plate coming in contact with a living body surface and fitted in the opening part of a suction cell which sucks the exudation liquid and an oscillator which oscillates the micro thin needle. SOLUTION: This exudation liquid sucking device is formed in such a way that a passage groove 5 is formed on the suction port 3 side of the passage plate 4 from a center in radial shape, and the passage plate 4 in which plural conical micro thin needles 6 are formed on an opening part 2 side is installed in the opening part 2 of the suction cell 1. Plural through ports 7 are formed among the micro thin needles 6 piercing through the passage groove 5. While, a passage port 8 is formed in the center of the passage plate 4, to which the suction port 3 is connected. A flat plate shape piezoelectric oscillator 10 is placed on the passage plate 4, and its center part is fixed. A hollow part 12 is provided in the center part of the piezoelectric oscillator 10 to evade a part equivalent to the passage port 8 of the passage plate 4. Two electrodes 11 to supply electric energy for excitation are installed in plane fashion on the upper surface of the piezoelectric oscillator 10, and wiring from the upper part of the suction cell to a connector 13 is performed.

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 exudate in a living body, and more particularly to a leachate suction device used for collecting a trace amount of body fluid without blood.

[0002]

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

Therefore, these measuring methods can be used in the fields of medicine, diagnosis and biochemistry, for example, for diagnosing diseases and measuring health by measuring the concentration of organic components contained in plasma, urine and the like. However, it is necessary to pay sufficient attention to the risk of infection and bleeding, as well as the pain of the patient associated with blood collection and the provision of medical labor.

Recently, a method of locally removing the stratum corneum of the skin to collect body fluid from the part and measuring the component concentration of this exudate with a sensor has been used as a sampling method for alleviating the pain on the patient side and the labor on the medical side. It has been developed. An example of this method is NEC Technical Report Vol. 16, No. 9 (1993) 83rd
From page 91 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 by the degree of the reaction. Is. A leachate suction device has been used to collect the leachate, which is the interstitial fluid required for this measurement.

FIG. 7 is a cross-sectional view of a conventional exudate suction device showing an example. The leachate collecting device disclosed in Japanese Patent Laid-Open No. 4-341241 is referred to as a spacer fixed by a frame 13 in the opening 2 that comes into contact with the skin of the suction cell body 1 for sucking the leachate as shown in FIG. It was characterized in that a nylon mesh 14 was incorporated, and the leachate was collected by exhausting from the suction port 3.

[0007]

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

The thickness and condition of the stratum corneum cannot be specified due to individual differences such as age, sex, 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, mechanically pressing the adhesive tape against the skin surface, mechanically scraping off the skin surface, and peeling work are repeatedly performed. As described above, due to individual differences, the required time varies and is not constant, and in some cases it may be painful.

The degree of removal of the stratum corneum affects the time for which the leachate is sucked and leached, and determines the leaching efficiency. For example, even the same person may require 15 minutes or 1 hour to obtain 10 μl of exudate.

Further, when removing the stratum corneum, pretreatment for cleaning such as degreasing and depilation is required depending on the site, and clinical treatment for suppressing inflammation after suction and leaching is required.

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

[0013]

A leachate suction device of the present invention has a suction port for sucking and decompressing the leachate from the surface of a living body and an opening on the side of the surface which is in direct contact with the surface of the living body. In the exudate suction device comprising a flow channel plate fitted and fixed in the opening and in direct contact with the surface of the living body, and a vibrator installed inside or outside the opening for vibrating the flow channel plate, The vibrator is installed on the suction port side of the path plate, and a plurality of microneedles and through holes are formed on the surface of the flow path plate that directly contacts the surface of the living body.

[0014]

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

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

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

[0017]

EXAMPLE A leachate suction device having such a structure has, for example, an outer diameter of the flow path plate 4 of 30 mm, a thickness of 0.5 mm, a length of the fine needle 6 of 30 μm, a needle diameter of 20 μm, and a pitch of 0.1 m.
If the diameter is m and the diameter of the through holes 7 is 50 μm, the numbers of the fine needles 6 and the through holes 7 formed in the flow path plate 4 are about 80,000, respectively. When the suction pressure is reduced from the suction port 3 (for example, 0.5 atm), the skin surface is depressurized via the flow channel 8, the flow channel 5, and the through port 7, and the flow channel 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 placed in contact is excited, and the fine needles 6 penetrate into the stratum corneum of the skin and penetrate the stratum corneum. Then, the tip of the fine needle 6 reaches at least the dermis where the interstitial fluid to be exuded exists. The thickness of the stratum corneum is said to be 10 to 30 μm although it varies depending on the individual, and the thickness of the dermis of the underlying tissue cells is several 10 μm. Since the fine needle 6 penetrates into the skin by the length of the needle, it does not reach the site where the capillaries are present and thus does not bleed. It is desirable that the tip of the fine needle 6 be sharp, but even if the amount of displacement is several μm, vibration is continued, so that it easily penetrates into the skin and stops at the surface of 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 the form of scales having a diameter of about several tens of μm. The diameters and pitches 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 or the like 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 leaches out between the fine needle 6 and the side surface of the skin. Fine needle 6 due to vibration
A space is temporarily generated between the skin and the skin contact surface, and the exudate is likely to be exuded.

Therefore, not only the work which has conventionally required a long time to remove the stratum corneum can be omitted, but there is an effect that the exudate exudation efficiency does not vary even if there are individual differences in the thickness of the stratum corneum. For example, when measuring the daily fluctuation of glucose concentration in blood, the required amount of exudate is 10μ.
If it is set to l, it takes about 15 to 30 minutes per time for each individual difference, but it can be stably reduced to 15 minutes or less. The time resolution of the changing glucose concentration is improved, and the accuracy of clinical diagnosis is also improved.

The piezoelectric vibrator 10 for exciting the flow path plate 4 has a size equivalent to the diameter of the flow path plate 4 of about 30 mm and is housed in the opening 2. Its shape is a circular flat plate, and if a ceramic sintered body such as barium titanate or lead zirconate titanate having a thickness of 0.5 mm is used,
Since it is possible to easily vibrate in the vertical direction from audible frequencies to ultrasonic waves and megasonics, it is possible to obtain a piezoelectric vibrator having a simple structure. In particular, it is clear from the principle that setting the operating frequency as high as 1 kHz or higher is more effective because it is less affected by the resonance frequency of the suction cell body.

FIG. 2 is a pattern diagram of electrodes of the piezoelectric vibrator of FIG. In this piezoelectric vibrator, as shown in FIG. 2, a plurality of electrode 11 patterns are radially formed independently. When operated so as to continuously apply a voltage between the electrodes 11 adjacent to each other, a displacement occurs in the direction in which the electrodes are arranged, and it is possible to uniformly vibrate from the vicinity of the center to the vicinity of the disk end. . In the structure shown in FIG. 1, since the central portion is fixed, the portion showing the largest amount of displacement is near the disk end, 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 exudate can be collected from the entire area of the flow channel plate, which has the effect of further improving the collection efficiency.

FIG. 3 is a sectional view showing a second embodiment of the exudate suction device of the present invention. As shown in FIG. 3, this exudate suction device is installed so that an annular piezoelectric vibrator 20 is fitted in the opening 2 of the suction cell body 1, and is further inscribed in the piezoelectric vibrator 20 to make a flow path. The plate 4 is fixed.

The leachate suction device having such a structure gives horizontal vibration to the flow path plate 4. That is, the annular piezoelectric vibrator 20 has, for example, a thickness of 2 mm, an inner diameter of 26 mm, and an outer diameter of 3 mm.
0 mm, and install electrodes on the inner and outer wall sides,
An alternating voltage is applied to this portion. The piezoelectric vibrator 20 gives vibration that pushes and pulls the flow path plate 4 with respect to the central axis, and at the same time serves as a source of action for moving the flow path plate 4 up and down. In addition, the effect of stretching and shrinking the skin surface itself also occurs. At this time, the fine needles 6 of the flow path plate 4 do not necessarily need to be sharp in the vertical direction,
Even in the arrow-shaped protrusions formed by patterning a thick film that is sharp in the horizontal direction and has a thickness of, for example, about 30 μm, it is possible to penetrate the stratum corneum.

Therefore, in addition to the same effects as those of the first embodiment, the effect of extending the skin surface and the vibration of the flow path plate 4 in the horizontal direction allow the fine needles 6 and the stratum corneum to be separated. The space generation is expanded, and further the leaching efficiency is 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, this exudate suction device is installed so that an annular piezoelectric vibrator 20 (inner diameter 2r) is fitted in the opening 2 of the suction cell body 1, and the piezoelectric vibrator 20 An annular pushing 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 which a similar taper angle is in contact with the flow path plate 4 provided on the outer circumference. In the third embodiment, an annular piezoelectric vibrator 2 having an inner diameter 2r is used.
When 0 is excited, its inner diameter reaches a maximum value of 2 (r + Δ
r), the vibration having the minimum value 2 (r−Δr) is repeated. Due to this radial expansion / contraction movement, the annular push-out portion 21 fixedly provided on the piezoelectric vibrator 20 also undergoes radial expansion / contraction movement, so that the flow path plate 4 in contact via the taper angle 25 is moved. It is structured to vibrate in the Z direction. Specifically, the radius r of the extruded portion 21 is reduced to r−Δr, so that the flow path plate 4 is extruded in the + Z direction (downward direction in the figure) through the tapered portion of the angle α, and the extruded portion is extruded. The distance (ΔZ) is ΔZ = Δr × tan α. When the radius of the extruded 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 vibration (ΔZ = ± Δr × tan α) in the Z direction. It has a structure.

In the third embodiment in which the taper angle (α) is provided, the displacement amount (Δr) of the piezoelectric vibrator 20 is enlarged. When the taper angle α is 45 degrees or more, the displacement amount Δr is enlarged. For example α
= 1.73 times at = 60 degrees, 2.75 times at α = 70 degrees,
When α = 80 degrees, it can be expanded to 5.67 times, and when α = 85 degrees, it can be expanded to 11.4 times. By using the piezoelectric vibrator 20 with Δr = 0.2 μm and setting the taper angle (α) to 85 degrees, approximately 2
A fine needle 6 having a stroke of μm could be obtained.
In order to smoothly vibrate the fine needles 6, it is important to improve the sliding of the taper portion, and the medicinal oil that is usually used to smooth the taper surface (desirably a mirror surface state) and to obtain a lubricating effect. It was effective to put a small amount of the like (preferably low viscosity) on the tapered surface.

By providing the leachate suction device with the function of enlarging the displacement amount as described in the third embodiment, it becomes possible to use a smaller piezoelectric vibrator, and the leachate suction device can be designed in a smaller size. Has the effect of facilitating.

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

FIG. 5 is a sectional view showing a fourth embodiment of the exudate suction device of the present invention. As shown in FIG. 4, this exudate suction device has a disk-shaped piezoelectric vibrator 30 installed and fixed around the suction port 3 outside the suction cell body 1. The flow path plate 4 is fitted in the opening 2 of the suction cell body 1, and the fine needles 6 and the through holes 7 are formed on the side of the flow path plate 4 on the opening 2 side. This is the same as 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 disk-shaped piezoelectric vibrator 30 installed outside the suction cell body 1. As a result, the entire suction cell body 1 is vibrated,
The fine needles 6 penetrate the stratum corneum, and the interstitial fluid can be leached from the through holes 7.

Therefore, in addition to the same effects as those of the leachate suction device shown in the first embodiment, the piezoelectric vibrator 30 is installed outside the suction cell body 1 to facilitate the assembly. Since it is not necessary to provide the interior of the opening 2, the difficulty of designing and manufacturing is reduced particularly with respect to the accuracy of the outer diameter dimension.

FIG. 6 shows a fifth exudate suction device according to the present invention.
3 is a cross-sectional view showing the embodiment of FIG. As shown in FIG. 6, this 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 flow path plate is fitted and fixed to the side surface of the opening. For example, assuming that the diameter of the opening is 2 having a diameter of 30 mm, the annular piezoelectric vibrator 40 has an inner diameter of 20 mm and an outer diameter of 25 mm. Then, reduce the radius by 1 and select the size to be attached to the flow path plate. The application electrodes for the ring-shaped piezoelectric vibrator 40 are provided on the upper and lower surfaces, and the piezoelectric vibrator 40 is arranged 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 4 μ, which is about four times that in the central portion, assuming that the portion on which the piezoelectric vibrator 40 is mounted is 1 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 needles 6 easily enter the stratum corneum, and conversely, there is an advantage that it can be easily driven even by applying a voltage with a small voltage.

Although the novelty of the configuration of the present invention has been described with reference to the embodiments, the invention is not limited to these. For example, a flat plate or ring-shaped piezoelectric vibrator was used, but the same effect can be obtained by combining them or installing them in a plane and dividing them into multiple pieces. 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 according to the dimension, but it was temporarily set to compare the effect with a conventional mesh. It is a size and can be arbitrarily selected without being particular about this.

Further, the shape of the fine needle has been described as a conical shape or an arrow shape, but a fine needle having a polygonal pyramid shape, a cylindrical shape, or a combination thereof can be easily penetrated into the stratum corneum when vibration is applied. You can

[0036]

As described above, according to the present invention, a plurality of fine needles are provided on the flow path plate which is brought into contact with the surface of the living body and fitted into the opening of the suction cell body for sucking the exudate. By installing a vibrator that vibrates the exudate, the exudate can be sucked and collected by a simple cleaning operation without removing the stratum corneum on the skin surface. Also, because the stratum corneum is not removed,
Conventionally, the extraction efficiency of the exudate varies greatly depending on the degree of removal of the stratum corneum, but this also disappears, and there is an effect that individual differences are reduced and stable extraction efficiency is obtained.

[Brief description of drawings]

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

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

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

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

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

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

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

[Explanation of symbols]

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

Claims (6)

[Claims] 1. A suction cell body having a suction port for suctioning and decompressing exudate from the surface of a living body, an aspiration cell body having an opening on the surface side that directly contacts the surface of the living body, and the living body fixed directly in the opening. In a leachate suction device comprising a flow channel plate that comes into contact with a surface and a vibrator installed inside or outside the opening for vibrating the flow channel plate, the vibration is applied to the suction port side of the flow channel plate. A leachate suction device, characterized in that a plurality of microneedles and through holes are formed on the surface of the flow path plate that directly contacts the living body surface, while the child is installed. 2. The exudate suction device according to claim 1, wherein the vibrator is a piezoelectric vibrator. 3. The exudate suction device according to claim 2, wherein the piezoelectric vibrator has a plurality of voltage applying electrodes radially arranged on one plane. 4. The piezoelectric vibrator is installed around the suction port in the upper part of the suction cell body.
The exudate suction device described. 5. The exudate suction device according to claim 1, wherein a ring-shaped oscillator is installed on the outer periphery of the flow path plate. 6. The exudate suction device according to claim 2, wherein the piezoelectric vibrator is installed inside a fulcrum of the flow path plate.