JP2012213475A - Ultrasonic contrast medium infusion set - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an infusion set of an ultrasonic contrast medium, which is easy to control volume and size of air bubble.SOLUTION: The medium infusion set includes an air bubble generator that generates an ultrasonic contrast medium from an air supersaturated water, where there is too much air to be soluble, by vibrating or flowing the water so as to cause a pressure drop so that bubbles are generated in the air supersaturated water. Thus, it is possible to infuse in vivo the ultrasonic contrast medium containing air bubbles.

Description

  The present invention relates to an ultrasonic contrast medium injection device.

Microbubbles have been used as a contrast agent for ultrasonic diagnosis in which ultrasonic waves are irradiated from outside the body and reflections are used to diagnose internal structures, blood flow, lesions, and the like. Since bubbles are unstable, ultrasonic contrast agents that have stabilized the bubbles by forming a shell with lipids, surfactants, albumin, etc. at the outer edge of the bubbles and containing the gas have been developed so far. It has been developed (Patent Document 1, Non-Patent Document 1).
In addition, in order to prevent gas components constituting bubbles from diffusing into body fluids such as blood as much as possible, a poorly water-soluble gas such as carbon fluoride is used instead of a gas having high solubility in water such as oxygen or carbon dioxide. (Non-Patent Document 1).

Japanese Patent No. 3614445

Fuminori Moriyasu, Hiroko Iijima, Video Information Medical, May 2006, p.570-578

  However, existing ultrasound contrast agents are adjusted immediately before administration, but there is a problem that the amount and size of bubbles are not easily controlled.

  Therefore, an object of the present invention is to provide an ultrasonic contrast agent injection device in which the amount and size of bubbles can be easily controlled.

The present inventors have found that microbubbles are generated by irradiating an ultrasonic solution to an aqueous solution (gas supersaturated water) in which a supersaturated amount of gas is dissolved, and based on this, the present invention relating to an ultrasonic contrast agent injection device is disclosed. It has been completed.
That is, the ultrasonic contrast agent injection device according to the present invention vibrates or flows gas supersaturated water in which a gas having a saturation dissolution amount or more is dissolved so that a pressure drop occurs, and bubbles are generated in the gas supersaturated water by the pressure drop. And a bubble generating device for generating an ultrasound contrast agent containing bubbles from the gas supersaturated water, and injecting the ultrasound contrast agent containing bubbles into a living body.

  In one embodiment of the present invention, the bubble generating device includes an ultrasonic vibrator that ultrasonically vibrates the gas supersaturated water.

In an embodiment of the present invention, the ultrasonic contrast agent injecting device communicates with the inside of the cylinder, a cylindrical container that stores the gas supersaturated water therein, a movable pusher that is inserted into the cylinder from one end of the cylindrical container. An injection tube,
The ultrasonic transducer ultrasonically vibrates the gas supersaturated water flowing through the injection tube.

  In an embodiment of the present invention, an ultrasonic absorber that suppresses transmission of ultrasonic vibrations to the gas supersaturated water inside the cylinder, which is provided between the ultrasonic transducer and the cylinder container, is further included.

  In one form of the present invention, the filter further includes a filter having a fine hole through which the ultrasonic contrast agent passes, and the filter removes bubbles exceeding a predetermined size included in the ultrasonic contrast agent.

  In one embodiment of the present invention, a substance that forms a lipid bilayer membrane in a bubble is applied to the micropores of the filter.

  In one embodiment of the present invention, the diameter of the fine pores of the filter is 1 μm or less.

  In one form of this invention, the temperature control apparatus which adjusts the temperature of the gas supersaturated water in the said bubble generation apparatus is further provided.

According to the present invention configured as described above, it is possible to provide an ultrasonic contrast agent injection device in which the amount and size of bubbles can be easily controlled.
That is, according to the injection device according to the present invention, since an ultrasonic wave can be irradiated outside the body to an aqueous solution (gas supersaturated water) in which a supersaturated amount of gas is dissolved, it is applied to the gas supersaturated water according to the intended diagnosis. The frequency and intensity of the ultrasonic vibration to be adjusted can be adjusted, and the amount and size of the bubbles can be easily controlled.

It is sectional drawing which shows typically the structure of the ultrasonic contrast agent injection apparatus of Embodiment 1 which concerns on this invention. It is sectional drawing which shows typically the structure of the ultrasonic contrast agent injection apparatus of Embodiment 2 which concerns on this invention. It is a block diagram which shows an example of a gas supersaturated water manufacturing apparatus. It is the schematic which shows an example of a gas supersaturated water manufacturing apparatus. It is the schematic which shows a part of gas supersaturated water manufacturing apparatus. (A)-(c) is the schematic which shows a part of gas supersaturated water manufacturing apparatus, respectively. (A)-(d) is the schematic which shows a part of gas supersaturated water manufacturing apparatus, respectively. It is the schematic which shows a part of gas supersaturated water manufacturing apparatus. It is a figure which shows the relationship between the production temperature of gas supersaturated water, and the amount of gas generation. It is a figure which shows the gas generation amount which produces | generates after gas supersaturated water is manufactured at each temperature of 4, 20, and 37 degreeC, and is made 37 degreeC. It is a figure which shows the change of the gas generation amount by a solvent. It is a figure which shows the change of the gas generation amount at the time of solvent mixing. It is a photograph which shows a mode that ultrasonic irradiation was carried out to gaseous supersaturated water, (a) is before irradiation, (b) shows the state after irradiation. It is a figure which shows the time change of the supersaturation degree of the air of gas supersaturated water, and the brightness | luminance in a silicon tube. It is a figure which shows the relationship between the supersaturation degree of the air of gas supersaturated water, and the maximum luminance after ultrasonic irradiation. A contrast image of a silicon tube cross section at a standardized luminance of 1.40 and a contrast image of a silicon tube cross section at a standardized luminance of 1.91 are shown. It is a figure which shows the relationship between the supersaturation degree of air, oxygen, a carbon dioxide, and nitrogen, and the maximum luminance after ultrasonic irradiation. A contrast image of a silicon tube cross section with a gas supersaturated water of oxygen with a supersaturation degree of 1.82 and a contrast image of a silicon tube cross section with a gas supersaturated water of nitrogen with a supersaturation degree of 1.95 are shown. It is a figure which shows the time-dependent change of the brightness | luminance in a silicon tube when gas supersaturated water is made to flow through the 40 volume% glycerol aqueous solution. The contrast image of the cross section of the silicon tube by the gas supersaturated water which flows in the glycerol 40vol% aqueous solution is shown. It is a figure which shows the time-dependent change of the injection | pouring speed | rate of gaseous supersaturated water, and the brightness | luminance in a silicon tube. The contrast image of the cross section of the silicon tube by the gas supersaturated water at each injection speed is shown. The size of microbubbles at ultrasonic frequencies of 50 kHz and 1 MHz is shown. The situation where an ultrasonic wave is irradiated by an ultrasonic probe from the outside of the agar phantom is shown.

Hereinafter, an ultrasonic contrast agent injecting apparatus according to an embodiment of the present invention will be described with reference to the drawings.
FIG. 1 is a cross-sectional view schematically showing a configuration of an ultrasonic contrast agent injection device according to Embodiment 1 of the present invention.
The ultrasonic contrast agent injecting apparatus according to the first embodiment is provided with an ultrasonic vibrator 1 that ultrasonically vibrates gas supersaturated water 6 in which a gas having a saturation dissolution amount or more is dissolved. As will be described later in detail, the gas supersaturated water 6 used in the ultrasonic contrast agent injecting apparatus according to the first embodiment generates minute bubbles due to high-speed vibration of the solution due to ultrasonic vibration or the like and pressure drop due to high-speed flow. The aqueous solution according to the inventors' invention adjusted as described above is not limited to ultrasonic vibration, and minute bubbles are generated by various physical stimuli that cause a pressure drop that causes cavitation. In addition, as a method of reducing the pressure by physical stimulation, in addition to vibration accompanied by microscopic position change of gas supersaturated water such as ultrasonic vibration, for example, a screw is rotated at high speed or a finely blown blow is used. For example, the gas supersaturated water is flowed at a high speed so as to be blown out from the outlet at a high speed to cause a pressure drop.
Hereinafter, a specific configuration of the ultrasonic contrast agent injection device according to the first embodiment will be described.

The ultrasonic contrast medium injecting apparatus of Embodiment 1 includes a cylindrical container 4 that accumulates gas supersaturated water 6 inside a cylinder, a movable pusher 5 that is inserted from one end of the cylindrical container 4 into the cylinder, and an injection that communicates with the inside of the cylinder. The ultrasonic vibrator 1 is provided so as to surround the outer peripheral portion of the injection tube 3, and the gas supersaturated water 6 flowing through the injection tube 3 is ultrasonically vibrated.
Further, in the ultrasonic contrast agent injecting apparatus according to the first embodiment, ultrasonic absorption that suppresses transmission of ultrasonic vibration to the gas supersaturated water 6 accommodated inside the cylinder between the ultrasonic transducer 1 and the cylinder container 4. A body 7 is further provided.

  Connected to the ultrasonic transducer 1 is an ultrasonic vibration control device 10 that sets the frequency and intensity of the ultrasonic transducer 1 to predetermined values. The ultrasonic vibration control device 10 has, for example, a memory in which information on the gas supersaturated water 6 to be used is stored. Based on the information on the gas supersaturated water 6, bubbles 6 a having a desired bubble diameter and bubble amount are generated. The frequency and intensity of the ultrasonic vibrator 1 are adjusted so as to occur in the gas supersaturated water 6.

  Although not shown in FIG. 1, the ultrasonic contrast agent injecting apparatus according to the first embodiment may further include a flow rate control device that controls the amount of movement of the movable pusher 5. By adjusting the flow rate of the gas supersaturated water 6 in the injection tube 3, it is possible to adjust the bubble diameter and the amount of bubbles of the bubbles 6 a generated in the gas supersaturated water 6.

  Furthermore, the ultrasonic contrast agent injection device according to the first embodiment is configured to generate the bubbles 6a outside the body and adjust the ultrasonic contrast agent to be injected into the body. It is also possible to attach a temperature control device that sets the temperature of the gas supersaturated water to a predetermined temperature. If the temperature of the gas supersaturated water at the time of generating bubbles can be adjusted, it is possible to efficiently generate bubbles, and control of the bubble diameter and the amount of bubbles becomes easy. In the present invention, the ultrasonic vibration control device 10 may have this temperature control function. In addition, what is necessary is just to make it the temperature suitable for inject | pouring the ultrasonic contrast agent containing a bubble into a body, when inject | pouring into a body.

  Moreover, since the ultrasonic absorber 7 which suppresses transmission of the ultrasonic vibration to the gas supersaturated water inside the cylinder is included between the ultrasonic vibrator 1 and the cylinder container 4, the gas supersaturated water inside the cylinder is stable. The ultrasound contrast agent can be produced and injected into the body in the required amount when needed.

In the present invention, various ultrasonic vibrators can be used as the ultrasonic vibrator 1, and examples thereof include piezoelectric ceramics, piezoelectric polymers, and piezoelectric thin films.
Further, various ultrasonic absorbers can be used as the ultrasonic absorber, and examples thereof include silicon rubber, expanded polystyrene, expanded polyurethane, and expanded rubber.

  As described above, the ultrasonic contrast agent injecting apparatus according to Embodiment 1 is configured to irradiate an aqueous solution (gas supersaturated water) in which a supersaturated amount of gas is dissolved outside the body. The frequency and intensity of the ultrasonic vibration applied to the gas supersaturated water can be adjusted without considering the influence, and the amount and size of the bubble 6a can be easily controlled according to the intended diagnosis. .

Embodiment 2. FIG.
As shown in FIG. 2, the ultrasonic contrast agent injecting apparatus according to the second embodiment of the present invention further includes a number of microscopic agents that allow the ultrasonic contrast agent including the bubbles 6a to pass through the ultrasonic contrast agent injecting apparatus according to the first embodiment. Except for further including a filter 2 having a hole, the configuration is the same as that of the ultrasonic contrast agent injection device of the first embodiment.
Thereby, in the ultrasonic contrast agent injection device according to the second embodiment, bubbles exceeding a predetermined size included in the ultrasonic contrast agent can be removed.

  The fine holes of the filter 2 of Embodiment 2 are set so as to have a bubble diameter corresponding to the target ultrasonic diagnosis (for example, adjusted to 1 μm or less). By using such a filter 2 to remove bubbles larger than the filter diameter or to reduce the variation in the bubble diameter to be poured out, it is possible to reduce the inspection error caused by the inappropriate bubble diameter.

In addition, the filter 2 of Embodiment 2 further applies a substance (for example, albumin) that can form a lipid bilayer on the inside of the micropores, the surface of the micropore outlet, or the surface with the micropore outlet. Thus, it is possible to provide a function of forming a lipid bilayer that encloses bubbles contained in the ultrasonic contrast agent.
This function can be easily realized by injecting lipid into the filter 2 from the lipid supply device 20 shown in FIG. In FIG. 2, the bubbles encased by the lipid bilayer membrane are shown with a symbol 6 b.
Thus, by providing the filter 2 with the function of forming a lipid bilayer that encloses bubbles, the lifetime of the bubbles can be improved, more accurate ultrasonic diagnosis is possible, and gas supersaturation is achieved. Expand the range of water selection.
As a method for confirming whether a lipid bilayer wrapping bubbles is formed, it is possible to confirm by a technique such as Dark Field microscopy and TEM in Non-Patent Document Kodamta etal. J. Electron Micorscopy 2010. By monitoring the formation state of the lipid bilayer membrane and feeding back the monitoring information to an ultrasonic control device or the like, it is possible to effectively and reliably form a lipid bilayer membrane that wraps bubbles.

  Various filters can be used as the filter 2. For example, a hollow fiber filter, a ceramic filter, a polymer membrane filter, and the like can be given.

  In the second embodiment, the filter 2 has a function of forming a lipid bilayer wrapping bubbles. However, the present invention is not limited to this, and the filter 2 is replaced with a lipid bilayer membrane. A forming apparatus may be provided.

  In addition, the ultrasonic contrast medium injecting apparatus of the present invention can be provided with a temperature control device that maintains an appropriate temperature for each part. For example, in addition to the temperature control device that adjusts the temperature of the gas supersaturated water when generating the bubbles 6a, the tube container 4 is used to keep the liquid temperature of the gas supersaturated water 6 injected into the tube container 4 at a temperature suitable for storage. By providing the temperature control device in the portion, for example, it is possible to keep the dissolved amount of gas constant and to prevent vaporization due to temperature change. In addition, by providing a temperature control device in the nozzle portion, by adjusting the temperature of the ultrasound contrast agent to about the body temperature (around 37 ° C.), due to a rapid temperature change when the ultrasound contrast agent enters the body It is also possible to prevent alteration of the ultrasound contrast agent (including changes in the bubbles themselves and changes in the dispersion state of the bubbles).

  Hereinafter, the gas supersaturated water 6 used suitably for the ultrasonic contrast agent injection device according to the present invention will be described.

<Gas supersaturated water>
The present inventors have found that microbubbles are generated by irradiating the gas supersaturated water with ultrasonic waves, and produced gas supersaturated water suitable for the ultrasonic contrast agent injection device of the present invention.
This gas supersaturated water generates microbubbles by ultrasonic irradiation, thereby enabling ultrasonic contrast.

  The gas supersaturated water is an aqueous liquid in which a gas is contained in excess of the saturated dissolution amount. Gas supersaturated water contains a supersaturated amount of gas.

The saturated dissolution amount, when referring to a gas, means the maximum volume that dissolves in a liquid under the environment for carrying out the present invention. The saturated dissolution amount of a gas in a liquid varies depending on the type of liquid and gas, temperature, atmospheric pressure, and the like. Therefore, the saturation dissolution amount differs depending on the environment even if the kind of gas and the liquid serving as the medium are the same.
For example, the saturation dissolution amount of oxygen at 1 atm. With respect to 1 L of water varies from 48.9 mL at 0 ° C., 37.5 mL at 15 ° C., 35.7 mL at 20 ° C., and 33.5 mL at 25 ° C.
Examples of saturated dissolution amounts include the following:
(1) The saturated dissolution amount of air in water at 0 ° C. and 0.1 MPa (about 1 atm) is 36.18 mg / L;
(2) The saturated dissolution amount of air in water at 20 ° C. and 0.1 MPa (about 1 atm) is 23.80 mg / L;
(3) The saturated dissolution amount of air in water at 25 ° C and 0.1 MPa (about 1 atm) is 21.95 mg / L;
(4) The saturated dissolution amount of air in water at 37 ° C and 0.1 MPa (about 1 atm) is 18.68 mg / L;
(5) The saturated dissolution amount of nitrogen in water at 0 ° C. and 0.1 MPa (about 1 atm) is 14.68 mg / L;
(6) The saturated dissolution amount of oxygen in water at 0 ° C. and 0.1 MPa (about 1 atm) is 14.16 mg / L;
(7) The saturated dissolution amount of hydrogen in water at 25 ° C. and 0.1 MPa (about 1 atm) is 14.39 mg / L.
The saturated dissolution amount of gas can be calculated from Henry's law.

An aqueous liquid is a solution whose solvent is water. The type of the aqueous liquid is not particularly limited and can be appropriately set by those skilled in the art. In the present invention, so-called isotonic solutions having the same osmotic pressure as cells may be used.
Examples of isotonic solutions include physiological saline, PBS (including PBS (+) and PBS (−)), 2.6% glycerol aqueous solution, and 5% dextrose aqueous solution.

As described above, since the saturated dissolution amount of the gas with respect to the liquid varies depending on the type of gas, temperature, atmospheric pressure, and the like, the volume of the gas contained in the gas supersaturated water also differs depending on the environment. For example, the volume of the gas contained in the gas supersaturated water can be measured at 25 ° C. and 1 atmosphere.
The gas supersaturated water can be prepared, for example, by mixing a gas with water under a pressure of 0.6 MPa. When physical stimulation (for example, ultrasonic stimulation, thermal stimulation, etc.) is applied to gas supersaturated water, the contained gas is separated from the solvent and appears as microbubbles.
For example, in gas supersaturated water in which the gas is air, microbubbles are generated by ultrasonic irradiation, and the total volume of the microbubble gas is 20 mL to 65 mL, 20 mL to 40 mL, or 30 mL to 40 mL (1 atm) in 1 L of water. , Volume at 25 ° C.).
Moreover, the gas supersaturated water whose gas is C ₃ F ₈ gas generates microbubbles by ultrasonic irradiation, and the total volume is 10 mL to 30 mL, 10 mL to 25 mL (1 atm, 25 ° C. in 1 L water). Volume).
The amount of gas contained in the gas supersaturated water can be expressed as a ratio to the saturated dissolution amount of the gas. For example, gas supersaturated water that contains 43.90mg / L of air at 25 ℃ and 0.1MPa (about 1atm) has a saturated dissolution amount of 21.95mg / L at 25 ℃ and 0.1MPa (about 1atm). Therefore, it can be expressed that the gas amount is doubled. Further, the ratio to the saturated dissolution amount may be expressed as the degree of supersaturation. That is, the supersaturation degree is 2 if a gas amount twice as much as the saturated dissolution amount at 25 ° C. and 0.1 MPa (about 1 atm) is included.
About the ultrasonic contrast agent used for this invention, the gas quantity contained in gas supersaturated water can be set suitably. For example, for angiography or blood flow imaging, after injection into the body, an aqueous solution containing air or nitrogen gas that is 1.5 times or more of the saturated dissolution amount, or oxygen gas or carbon dioxide gas that is 1.1 or more times the saturated dissolution amount. An impregnated aqueous solution can be used. Since the lower limit of the degree of supersaturation that can be contrasted was 1.1 or 1.5 with four types of gases with different properties (see Fig. 16), other gases should contain more than 1.5 times the saturated dissolution amount. When an aqueous solution is used for imaging, it can be estimated that imaging is possible. For example, gas containing 1.5 to 4 times, 1.5 to 3 times, 1.5 to 2 times, 2 times to 4 times or 3 times to 4 times the saturated dissolution amount Aqueous solutions can be used for imaging.

The gas may be easily soluble or hardly soluble, and when water is used as the liquid, it is a high gas even if it has a lower solubility in water than air or air. Also good. Examples of gases that can be used in the present invention include fluorocarbon, sulfur hexafluoride, air, oxygen, nitrogen, carbon dioxide, rare gases (helium, neon, argon, etc.), hydrogen, chlorine, methane, propane, butane, and monoxide. Nitrogen, nitrous oxide, and ozone are mentioned, and any mixed gas thereof may be used. Examples of fluorocarbons include CF ₄ , C ₂ F ₆ , C ₃ F ₆ , C ₃ F ₈ , C ₄ F ₆ , C ₄ F ₈ , C ₄ F ₁₀ , C ₅ F ₁₀ , C ₅ F ₁₂ , C ₆ F ₁₄ and the like.

In the gas supersaturated water, microbubbles are generated by ultrasonic irradiation. The ultrasonic irradiation is performed by using any device known to those skilled in the art, such as Sonitron 2000V, Sonopor 4000, Sonovista MSC1585 probe (manufactured by Mochida Siemens), ultrasonic bath VS-F100 (manufactured by Velvo-clear), and the like. Can be given. Instead of ultrasonic irradiation, other physical stimuli can be applied to generate microbubbles in the gas supersaturated water. The physical stimulus is not particularly limited as long as it is a stimulus that causes cavitation, and examples thereof include a vibration stimulus and an impact stimulus.
A person skilled in the art can appropriately set the intensity and frequency of the ultrasonic stimulation.
For example, the intensity of the ultrasound ^{0.06~0.1W / cm 2, 0.03~1W / cm} 2, may be set with 0.03~5W / cm ² or 0.5~10W / cm ² . Moreover, you may set the frequency of an ultrasonic wave in the range of 50 kHz-3.4 MHz, 50 kHz-1 MHz, 50 kHz-5 MHz, or 50 kHz-10 MHz, for example.

A microbubble is a microbubble. The size of the microbubbles is not particularly limited, but the diameter may be 1 nm to 1000 μm, 10 nm to 100 μm, 10 nm to 10 μm, 100 nm to 10 μm, or 1 μm to 10 μm. For example, the microbubbles may have a diameter of 1 μm or more and 20 μm or less.
The density of microbubbles generated by ultrasonic irradiation is not particularly limited, and may be, for example, 1 × 10 ⁶ to 1 × 10 ⁹ or 1 × 10 ⁷ to 1 × 10 ⁸ in 1 mL of the solution.

The gas supersaturated water used in the present invention may or may not have bubbles surrounded by a shell. Therefore, the gas supersaturated water used in the present invention includes albumin, γ globulin, gelatin, collagen, egg-derived substances (for example, hydrogenated egg yolk), lipids (for example, phosphatidylserine, phosphatidylserine sodium, etc.) Phospholipids), polymers (eg, polysaccharides (eg, chitosan or chitin), PLA, PLGA, etc.), sugars (eg, β-lactose, galactose), fatty acids (eg, palmitic acid), surfactants, and / or Liposomes may or may not be included.
Further, the gas supersaturated water used in the present invention includes albumin, γ globulin, gelatin, collagen, egg-derived substances (eg, hydrogenated egg yolk), lipids (eg, phospholipids such as phosphatidylserine and phosphatidylserine sodium), polymers ( For example, with or without polysaccharides (eg, chitosan or chitin), PLA, PLGA, etc., sugars (eg, β-lactose, galactose), fatty acids (eg, palmitic acid), surfactants, and / or liposomes May be.

In the present invention, the gas supersaturated water is, for example, the following steps:
(I) a step of pumping the liquid;
(Ii) injecting a gas into the pumped liquid;
(Iii) pressurizing the liquid into which the gas has been injected to dissolve the gas; and (iv) reducing the pressure to atmospheric pressure while pumping the liquid in which the gas is dissolved.
It is manufactured by the method containing.
FIG. 3 shows an example of a procedure for creating gaseous supersaturated water.
The temperature at which the steps (i) to (iv) are performed is not particularly limited. For example, if water is used as the solvent, the gas supersaturated water can be prepared at 0 ° C. to 100 ° C. existing as a liquid.
In order to increase the generation amount of microbubbles, it is preferable to create at a lower temperature if the pressure during pressurization is constant.
The inventors of the present invention have confirmed through experiments described later that the amount of microbubbles generated increases as the temperature at which the steps (i) to (iv) are performed is lower.
For example, if the solvent is water, microbubbles can be obtained by performing the steps (i) to (iv) at a low temperature at which the aqueous solution does not freeze, 0 ° C to 10 ° C, 4 ° C to 20 ° C, or 4 ° C to 10 ° C. The generation amount of can be increased.
Moreover, it is preferable that the said process is implemented at the temperature lower than use temperature.
In general, when a drug is applied to a living body or a cell, it is assumed that the drug is used at about 37 ° C. Therefore, gas supersaturated water is used at a temperature lower than 37 ° C (for example, a temperature higher than 0 ° C and lower than 37 ° C). You may create it.
The present inventors carried out the steps (i)-(iv) at 4 ° C. and the composition obtained by performing the steps (i)-(iv) at 37 ° C., which is an assumed use temperature, through experiments described later. Comparison with a composition heated to 37 ° C. confirmed that the latter produced more microbubbles. Thus, the present invention, in one embodiment, at a temperature lower than 37 ° C. (for example, a temperature higher than 0 ° C. and lower than 20 ° C., higher than 0 ° C. and lower than 10 ° C., or higher than 4 ° C. and lower than 10 ° C.) The manufacturing method of gaseous supersaturated water including implementing the process of said (i)-(iv) is provided.

Moreover, manufacture of gaseous supersaturated water can be manufactured mechanically using an apparatus. For example, a liquid input part that takes in liquid from a liquid supply source such as a water supply pipe or a liquid storage tank, a gas supply part that supplies gas to the liquid that has entered from the liquid input part, a gas-liquid mixing part that mixes gas and liquid, A pressure unit that pressurizes the liquid supplied with gas, a gas separation unit that separates excess gas from the gas-liquid mixture, and an atmospheric pressure so that the gas stays in the pressurized gas-liquid mixture And a discharge part that discharges the reduced pressure solution, and each part can be manufactured using an apparatus that is connected to the flow path.
The apparatus may be an apparatus that continuously discharges a gas-dissolved liquid that does not generate bubbles exceeding 1 μm in diameter from the outflow side of the decompression unit. Therefore, the gas supersaturated water may be an aqueous solution free of bubbles exceeding 1 μm in diameter.
An example of such an apparatus is a manufacturing apparatus X as shown in FIG.
FIG. 3 is a block diagram illustrating an example of a production apparatus X for gas supersaturated water. The apparatus X for producing gas supersaturated water includes a gas-liquid mixing unit 53 that mixes the gas Gs and the liquid Lq, a pressurizing unit 51 that pressurizes the mixed gas-liquid, and excess gas from the mixed gas-liquid. And a pressure reducing part 55 for reducing the pressure of the gas-liquid mixture that has been mixed and pressurized, and finally gas supersaturated water is obtained.

  FIG. 4 is a schematic view showing a specific example of the production apparatus X for gas supersaturated water. The apparatus X of FIG. 4 pumps liquid and continuously produces gas supersaturated water. The liquid inlet 63 receives liquid from a liquid supply source such as a water supply pipe or a liquid storage tank, and the liquid inlet 63. The gas supply unit 52 that supplies gas to the liquid that has entered from, the pressurizing unit 51 that pressurizes the liquid supplied with the gas, the gas-liquid mixing unit 53 that mixes the gas and the liquid, and the liquid in which the gas-liquid is mixed A gas separation unit 54 that separates excess gas from the gas-liquid mixture, a decompression unit 55 that decompresses the pressurized gas-liquid mixture to atmospheric pressure, and a discharge unit that ejects the decompressed gas-liquid mixture 57, and each part is provided connected to the flow path 56.

  The flow path 56 connects each part of the apparatus X, each part, and the outside, and flows a liquid from the upstream to the downstream, and is configured by a tubular body such as a pipe. The pressurizing unit 51, the gas-liquid mixing unit 53, the gas separation unit 54, and the decompression unit 55 are arranged in this order from the lower side to the upper side in a tapered cylindrical casing 62 whose diameter decreases toward the upper side. Is contained. The flow path 56 includes a flow path 56 a on the upstream side of the housing 62, a flow path 56 b in the housing, and a flow path 56 c on the downstream side of the housing 62. The flow path 56b is formed so that the liquid flows upward in the entire casing.

  The liquid inlet 63 is for introducing liquid into the apparatus from a liquid supply source outside the apparatus X. In the form of FIG. 4, the liquid inlet 63 is configured as an inlet of a tube body of the flow path 56a connected to the liquid supply source. Has been. The liquid inlet 63 may be provided with an adjustment valve or the like that can be opened and closed to adjust the inflow amount and pressure of the liquid.

  The gas supply unit 52 is connected to a flow path 56 (flow path 56a or 56b) or the like through which the liquid flows, and supplies and injects the gas to the liquid. Yes. For example, when air is injected as a gas, the gas supply unit 52 can be formed by connecting the other end of the tube whose one end is open to the atmosphere to the flow path 56. Or as gas, fluorocarbon, sulfur hexafluoride, air, oxygen, nitrogen, carbon dioxide, rare gas (helium, neon, argon, etc.), chlorine, methane, propane, butane, nitric oxide, nitrous oxide, ozone, hydrogen When supplying gas etc., the gas supply part 52 can be formed by connecting a cylinder filled with these gases to the flow path 56. Moreover, when supplying ozone, you may make it connect the gas supply part 52 to an ozone generator, and supply the ozone produced | generated from air. The connection position of the gas supply unit 52 to the flow path 56 may be a position upstream of the gas-liquid mixing unit 53. In the case where the pressurizing unit 51 and the gas-liquid mixing unit 53 are formed as a single unit and configured by the pump 61 as in this apparatus, the pressurizing unit 51 and the gas-liquid mixing unit 53 are connected to the flow path 56 on the upstream side of the pressurizing unit 51. Further, when the pressurizing unit 51 and the gas-liquid mixing unit 53 are configured separately, the pressurizing unit 51 and the gas-liquid mixing unit 53 may be connected to the flow path 56 upstream of the pressurizing unit 51 or downstream of the pressurizing unit 51. Either of them may be connected to the flow path 56 on the side.

  Here, in the case of attaching the drug to the microbubbles generated by ultrasonic irradiation, the drug may be dispersed and mixed in advance, and the liquid may be sent to the liquid inlet 63 to produce gas supersaturated water. After that, the drug may be dissolved.

  The pressurizing unit 51 pumps the liquid. For example, like this device, the pressurizing unit 51 can be configured by a pump 61 that pressurizes the liquid sent from the liquid supply source and sends it to the downstream side. When the pump 61 is used, the liquid stored in the liquid storage tank at normal pressure may be pumped up by the pump 61.

  The gas-liquid mixing unit 53 mixes the pumped liquid and the gas injected into the liquid, and makes the gas into fine bubbles by pressurization to disperse and mix in the liquid. The gas-liquid mixing unit 53 may be configured by applying a stirring force by changing the cross-sectional area of the flow path, or if the liquid is flowing through the flow path 56 with the liquid being stirred, 56 can also be configured. In the form of FIG. 4, the pressurizing unit 51 and the gas-liquid mixing unit 53 are combined and provided with a pump 61. In the gas-liquid mixing unit 53, the liquid and the gas are mixed under high pressure conditions.

By the pump 61 constituting the pressurizing unit 51 and the gas-liquid mixing unit 53 as described above, a pressure is rapidly applied to the liquid into which the gas has been injected, and the gas exceeding the saturated dissolution amount is dispersed in the liquid. Further, when the pressure is increased by a sudden pressure change, the pressure rate ΔP ₁ / t (ΔP ₁ : pressure increase, t: time) becomes 0.17 MPa / sec or more, and the gas-liquid mixing unit 53 By setting the hydraulic pressure when being sent out to the gas separation unit 54 from 0.15 MPa or more, the gas exceeding the saturation dissolution amount can be dispersed in the liquid. Considering the substantial pressurization condition, the upper limit of the pressurization rate ΔP ₁ / t is 167 MPa / sec, and the upper limit of the pressure of the pressurized aqueous solution is 50 MPa.

  FIG. 5 is a schematic diagram of a main part showing an example of a specific form of the pump 61. The pump 61 a pressurizes the liquid by the rotation of the rotating body 71, and the rotating blades 72 attached to the rotating body 71 are continuously rotated from the pump inlet 76 to the pump 77 through the pump passage chamber 73. The liquid is sent out and pressurized in the flow direction. In FIG. 5, the white arrow indicates the flow direction in the liquid direction, and the solid line arrow indicates the rotation direction of the rotating body 71. The pump 61a includes four rotating blades 72. Further, the rotating shaft 75 of the rotating body 71 is arranged so as to be offset toward the pump outlet 77 side from the cylindrical center of the pump wall 74 formed in a cylindrical shape, and is provided as an eccentric shaft. The volume of the second flow path chamber 73b of the pump flow path chamber 73 is formed smaller than the volume of the first flow path chamber 73a due to the eccentricity of the rotary shaft 71, and the pump flow path chamber is arranged along the liquid flow direction. The volume of 73 is gradually reduced.

Then, the liquid sent out to the pump flow path chamber 73 is sent out and pressurized by the rotor blades 72, and the large bubbles B _B are subdivided by a sudden pressure change, and the fine bubbles B _N are dispersed in the liquid. The That is, the liquid sent from the first flow path chamber 73a to the second flow path chamber 73b along with the rotation of the rotating body 71 is rapidly compressed and pressurized as the volume of the pump flow path chamber 73 becomes smaller. Bubbles _BN are generated by the pressure. Further, in the illustrated pump 61a, a shearing force is applied when the liquid passes between the inner surface of the pump wall 74 and the tip of the rotary blade 72, and the liquid is pressurized while being sheared by the clearance. At this time, the gas (large bubbles B _B ) mixed in the liquid is sheared by the shearing force applied to the liquid to become finer bubbles (B _N ). Here, narrowest part distance, i.e. the clearance distance L _C between the inner surface of the pump wall 74 and the inner surface of the rotor blades 74 and the distal end portion of the rotary blade 72 is preferably 5Myuemu～2mm. Thus, according to the pump 61a using the rotating body 71, the rotating body 71 can be pressurized with a strong force suddenly and the gas injected into the liquid can be sheared to form fine bubbles. In the pump 61, the high-pressure liquid contains a gas at a high concentration.
The rotational speed of the rotating body 71 of the pump 61 is preferably 100 rpm or more. At this time, it becomes 1/2 or more in 0.3 seconds. By having such a rotation speed, a gas exceeding the saturation dissolution concentration can be injected into the liquid.

  The pressurization by the pressurization unit 51 and the gas mixing unit 53 can be performed multiple times by providing a plurality of pressurization units 51 or gas-liquid mixing units 53. Specifically, the pressurizing part 51 can be constituted by a pump 61 as shown in FIG. 4, and the gas-liquid mixing part 53 can be constituted by one or two or more pumps 61 or a venturi pipe.

  The gas separation unit 54 removes a gas that is not finely mixed or dissolved in the liquid from the liquid in which the gas is mixed as described above. Such excess gas exists as bubbles having a relatively large diameter, and if the bubbles are removed, the excess gas can be separated and removed.

  The gas separation unit 54 can be configured by a tubular body or the like in which bubbles are lifted and removed by their own buoyancy. Since the removed bubbles become gas and accumulate on top. The removed gas can be removed by the gas removing unit 58. Bubbles of a size exceeding 1 μm in diameter rise due to buoyancy and can be removed.

  Specifically, the gas separation unit 54 can be configured as shown in FIG. (A) is formed so as to be substantially horizontal (on a plane substantially perpendicular to the direction of gravity) on the ground surface, and the bubbles B in the liquid Lq are raised to the liquid surface by the buoyancy to remove the bubbles B. An example of the tube is shown. Further, (b) is formed so that the shape is an inverted L shape when viewed from the front, and the flow direction of the liquid Lq is changed from the horizontal direction to the downward direction (substantially the same direction as the gravitational direction), thereby causing bubbles in the liquid Lq. An example of a tubular body in which B is raised to the liquid level by its buoyancy to remove bubbles B is shown. Further, (c) shows a tubular body in which the flow direction of the liquid Lq is set downward (substantially the same direction as the direction of gravity), and the bubbles B in the liquid Lq are raised to the liquid surface by buoyancy to remove the bubbles B. An example is shown. The bubbles separated by the gas separation unit 54 are discharged to the outside from a gas removal unit 58 formed of a tubular body or the like.

The decompression unit 55 gradually reduces the pressure of the liquid mixed with gas to atmospheric pressure without generating large bubbles. When the liquid mixed with the gas by pressurization as described above is in a high pressure state and is discharged to the outside as it is under atmospheric pressure, cavitation may occur due to a rapid pressure drop. Therefore, the pressure is reduced after the pressure reducing section 55 gradually reduces the pressure to atmospheric pressure. The depressurization unit 55 is configured to depressurize the upper limit of the depressurization speed ΔP ₂ / t (ΔP ₂ : depressurization amount, t: time) over the entire area of the pipe while sending a liquid mixed with gas. ing. Thereby, the solution can be taken out without generating cavitation.

The decompression section 55 can be configured as shown in FIG. 7, and specifically, the flow path 56 whose flow path cross-sectional area gradually decreases as shown in FIG. In this way, the flow path 56 whose flow path cross-sectional area continuously decreases gradually, or the gas-liquid mixing in the high pressure state (P ₁ ) due to the pressure loss in which the pressurized liquid flows in the flow path 56 as shown in (c). The liquid pressure is gradually reduced (P ₂ , P ₃ ,...), And the flow is performed as shown in the flow path 56 or (d) whose length (L) is adjusted so as to reduce the pressure to the atmospheric pressure (Pn). A plurality of pressure regulating valves 59 provided in the passage 56 can be used.

For example, when the decompression section 55 as shown in FIG. 7A or 7B is used, the flow path 56 upstream of the decompression section 55 has an inner diameter of 20 mm, and the decompression section 55 has a length of about 1 cm. -10 m, and the inner diameter can be gradually reduced from 20 mm to 4 mm, whereby the cross-sectional area of the channel can be reduced. In addition, the decompression part 55 can set an inlet inner diameter / outlet inner diameter = about 2-10, or can set the inner diameter reduction | decrease value per cm to about 1-20 mm. At this time, when the gas-liquid mixture is sent to the decompression unit 55 at a flow rate of 4 × 10 ⁻⁶ m / s or more, the decompression rate can be reduced to 1.0 MPa without generating cavitation at a decompression rate of 2000 MPa / sec or less. Can be reduced to atmospheric pressure.

  The decompressed liquid is discharged from the discharge liquid 57 to the outside. At this time, as shown in FIG. 8, an extension flow path 60 can be provided between the flow path 56 b and the flow 56 c in order to ensure a sufficient pressure of the liquid in the pressurizing unit 51. That is, the total pressure loss including the decompression unit 55 is calculated, the pressure required to pressurize the liquid and gas in the gas-liquid mixing unit 53 by the indentation pressure from the pressurization unit 51, and the total pressure loss The extension channel 60 may be added to the channel 56 by adjusting the channel length so that a pressure loss of this difference occurs. In order to secure the indentation pressure, it may be possible to provide a throttling portion or the like. However, if the indentation pressure is adjusted by the throttling portion or the like, bubbles may collapse due to a sudden pressure change. However, if the extended flow path 60 is provided in this way, gaseous supersaturated water can be discharged without cavitation.

In the apparatus X configured as described above, the gas supplied from the liquid inlet 63 is supplied with gas by the gas supplier 52 and injected. Then, the liquid into which the gas has been injected is subjected to a pressurization rate ΔP ₁ / t (ΔP ₁ : pressure increase amount, t) of 0.17 MPa / sec or more by the pressurizing unit 51 and the gas-liquid mixing unit 53 configured by the pump 61. : Time) to make the liquid pressure 0.15 MPa or more. That is, the pressure of the liquid when being sent from the gas-liquid mixing unit 53 to the gas-liquid separation unit 54 is 0.15 MPa or more. Thereafter, excess gas in the liquid is removed by the gas separation unit 54, and then the pressure is reduced to a maximum pressure reduction rate of 2000 MPa / sec or less ΔP ₂ / t (ΔP while sending the liquid to the pressure reduction unit 55 and the downstream flow path 56. ₍₂ : reduced pressure amount, t: time), the pressure is gradually reduced to atmospheric pressure. Thereby, gaseous supersaturated water can be continuously generated without the occurrence of cavitation.

  The flow path 56 on the downstream side of the gas-liquid mixing part 53 can be formed in a tube having an inner diameter of about 2 to 50 mm. Thereby, gas supersaturated water can be discharged with a relatively thick channel cross-sectional area, and clogging of piping as in the case where the channel 56 is constituted by a narrow channel can be prevented.

  And the gas supersaturated water discharged from the discharge part 57 is processed into the formulation of a suitable dosage form. For example, it can be enclosed in a syringe for intravenous administration, packed in an ampoule or vial for oral administration, or enclosed in a bag for transdermal administration. Since the preparation produced in this manner is stably present without generating bubbles even in the container, a large amount can be easily and efficiently obtained without the need for preparation of bubbles when necessary. Bubbles can be administered into the body.

  The gas supersaturated water used in the present invention can be appropriately formulated by those skilled in the art as an ultrasonic contrast agent. In addition to the gas supersaturated water that can be prepared as described above, the ultrasound contrast agent can contain an additive if necessary. Examples of the additive include a pH adjuster (for example, hydrochloric acid, citric acid and the like), a preservative (for example, p-hydroxybenzoate such as isobutyl paraoxybenzoate), an antioxidant (for example, ascorbic acid and tocopherol). Etc.), buffering agents (for example, sodium bicarbonate, sodium carbonate, phosphoric acid, etc.), viscosity enhancers (for example, sorbitol, sucrose, etc.), and osmotic pressure adjusting agents (for example, sugar, sugar alcohol, etc.).

The biological tissue image creation method using the ultrasonic contrast agent described above utilizes the fact that the acoustic impedance varies depending on the boundary surface of the biological tissue or the structure of the organ. Here, the target biological tissue is not particularly limited, and examples thereof include blood vessels, heart, liver, and kidney. The living body can be a mammalian living body, for example, a human. The acoustic impedance is expressed as the product of the density of the propagating medium and the speed of sound. For example, the propagation velocity of sound in the air (20 ° C) is 344 m / s, the density is 1.205 kg / m ³ , the propagation velocity of water (20 ° C) is 1482 m / s, and the density is 999.69 kg / m ³ . The sound propagation speed of the living tissue is, for example, adipose tissue 1450 m / s, blood 1570 m / s, bone (skull) about 4080 m / s, density is adipose tissue 920 kg / m ³ , blood 1060 kg / m ³ , bone 2010 kg / m ³ Degree. As can be understood from the numerical values exemplified here, the acoustic impedance differs depending on the boundary surface of the living tissue or the structure of the organ, and an image of the living tissue can be created using this.
When ultrasonic waves are applied to the microbubbles, the ultrasonic waves are reflected by the microbubbles. In the living body, the acoustic impedance of the microbubbles is greatly different from that of the living tissue. Therefore, the portion where the bubbles are present is emphasized and displayed due to the difference in the acoustic impedance. Therefore, the acoustic impedance difference imaging can be effectively used by using an ultrasonic imaging apparatus well known to those skilled in the art (for example, the ultrasonic diagnostic apparatus Sonovista MSC1585 manufactured by Mochida Siemens).
Further, when a sound wave having a wavelength sufficiently longer than the diameter is incident on a bubble in the liquid, the bubble performs respiratory vibration while maintaining isotropic property. Further, it is known that the respiratory vibration increases in amplitude at a specific frequency according to the bubble diameter. This phenomenon is called resonance. The density of the [rho ₀ liquid, hydrostatic pressure of the p ₀ at infinity, the incident sound pressure of p _a, R ₀ and R equilibrium value and the instantaneous value of the bubble radius, when the specific heat ratio of the gas inside gamma, resonance The frequency ω ₀ is represented by the following formula:

Under strong driving conditions, a nonlinear phenomenon appears remarkably in bubble vibration, so resonating microbubbles can use harmonic and sub-harmonic information for imaging in addition to the contrast effect of normal imaging, A further contrast effect is obtained and efficient. When the ultrasonic contrast agent used in the present invention is irradiated with 1 MHz ultrasonic waves to generate microbubbles, the bubble diameter is 1 μm, so the resonance frequency is calculated to be about 10 MHz. This frequency is a frequency band used in an ultrasound contrast apparatus well known to those skilled in the art, and harmonic or sub-harmonic imaging can be effectively utilized using such a well-known apparatus.
In this specification, the ultrasonic echo means an ultrasonic wave generated as a result of reflection or scattering of an ultrasonic wave incident on a substance to be examined.
The reception of ultrasonic echoes, the creation of tissue images, and the like can be performed by an ultrasonic contrast apparatus well known to those skilled in the art.

As a specific example,
An ultrasound imaging method or an ultrasound diagnostic method,
(I) a step of administering an ultrasound contrast agent containing air bubbles to a living body;
(Ii) irradiating a blood vessel at a desired site with ultrasound;
(Iii) receiving an ultrasound echo reflected or scattered by microbubbles; and (iv) creating an ultrasound image based on the received ultrasound;
Can be mentioned.
Ultrasound contrast includes irradiating a living body with ultrasonic waves and imaging living tissue using ultrasonic waves reflected or scattered from the living body. Ultrasound diagnosis includes determining the presence or absence of a disease based on the image, determining the type of disease, and the like.
In addition, a person skilled in the art can appropriately set how to perform administration of an ultrasonic contrast agent, irradiation of ultrasonic waves for generating microbubbles, and reception of ultrasonic echoes. For example, the ultrasound contrast agent can be administered intravenously, intraarterially, subcutaneously, or intradermally.
The ultrasonic contrast agent injection device shown in FIG. 1 or 2 can be used when the above-described ultrasonic contrast method or ultrasonic diagnostic method is performed.

  EXAMPLES Hereinafter, although an Example demonstrates this invention further, this invention is not limited to these.

Example 1
[Production of gas supersaturated water]
Using the device X, various gases described below were used as the gas, and the liquid described later was used as the liquid to produce gas supersaturated water.
As the device X, the one having the configuration of FIG. 4 in which the gas-liquid mixing unit 53 is configured by a pump 61 was used. As the pump 61, a pump 61a as shown in FIG.

The ratio of gas to liquid (injection amount of gas to liquid) was set to 1: 1 by volume ratio (volume ratio). Moreover, the rotation speed of the rotary body 71 of the pump 61 was set to 1700 rpm. Under this condition, after gas is injected into water at atmospheric pressure (0.1 MPa), the gas is pressurized at a pressurization rate ΔP ₁ /t=28.3 MPa / sec, from the gas-liquid mixing unit 53 to the gas separation unit 54. The pressure of the aqueous solution at the time of delivery became 0.6 MPa. Note that, under such conditions, the gas is injected into the liquid exceeding the saturation dissolution concentration.

  In addition, the flow path 56 (56b) on the upstream side of the decompression unit 55 has an inner diameter of 20 mm. As the decompression unit 55, one having an inner diameter that gradually decreases in three stages as shown in FIG. 7A is used. Specifically, the inner diameter is 14 mm, 8 mm, 4 mm, and each length is about 3.3 mm (decompression). The part 55 was composed of three channel pipe parts having a total length of about 1 cm. Further, a hose having an inner diameter of 4 mm (outer diameter of 6 mm) is used as the flow path 56 and the extension flow path 60 on the downstream side of the decompression unit 55, and the combined length of the downstream flow path 56 and the extension flow path 60 has a length. It was set to be 2 m. Under these conditions, the decompression unit 55 decompresses the aqueous solution at a maximum decompression speed of 60 MPa / sec and a time of 0.0025 seconds, and further, in the downstream channel 56 and the extension channel 60, 1 MPa / sec, a time of 0.5 The aqueous solution was depressurized in seconds, and gas supersaturated water was obtained from the hose tip by irradiation with ultrasonic waves depressurized to atmospheric pressure (0.1 MPa).

[Measurement of the amount of gas generated]
Gas supersaturation by using pure water (ultra pure water) as a liquid and air as a gas, and pressurizing at 0.6 MPa as described above at 4 ° C., 20 ° C., and 37 ° C. to include air in the ultra pure water. Created water. Sealing was performed immediately after preparation, and a part was heated to 37 ° C., and then the aqueous solution was adjusted to 25 ° C. The amount of gas (air) contained in an excess amount in the aqueous solution is changed to the following (1) to (4):
(1) Gas supersaturated water is sealed in a gas barrier bag made of nylon resin (As One 5-5665-01);
(2) Leave the aqueous solution sealed in the gas barrier bag (As One 5-5665-01) on a hot plate at 45 ° C. for 2 hours;
(3) It was allowed to stand at room temperature (25 ° C.) for 3 hours; and (4) The gas present in the gas barrier bag (As One 5-5665-01) was collected and its volume was measured.
As a result, the amount of gas generated from the aqueous solution was the largest at 4 ° C., and decreased in the order of 20 ° C. and 37 ° C. (see FIG. 9). If prepared at 4 ° C, approximately 60 mL of gas is contained in 1 L of water, if prepared at 20 ° C, approximately 40 mL of gas is included in 1 L of water, and if prepared at 37 ° C, approximately 20 mL of gas is included in 1 L of water. These appeared as microbubbles by application of ultrasonic waves. The amount of gas generated from the aqueous solution produced at 4 ° C. and 20 ° C. was slightly decreased by heating to 37 ° C., but the amount of gas generated was still larger than that of the aqueous solution produced at 37 ° C. (FIG. 10).
Therefore, it became clear that the lower the production temperature, the greater the amount of gas generated, and that the temperature at the time of creation contributed more to the decrease in the amount of gas generated than the temperature increase after creation. When applied to a living body or a cell at 37 ° C., it was shown that the amount of gas generated can be increased by heating after preparation at a low temperature.

[Gas generation in various aqueous solutions]
Using ultrapure water, physiological saline or phosphate buffer (PBS (+)) as the liquid, using air as the gas, and pressurizing at 0.6 MPa according to the method of Example 1 at 4 ° C. Gaseous supersaturated water was prepared by including in water. Sealing was performed immediately after creation, and then the amount of gas present in the aqueous solution was set to 25 ° C., and the amount of gas generated was measured (see FIG. 11).
In addition, 10-fold concentrated saline (10 × saline), 10-fold concentrated PBS (+) (10 × phosphate buffer) or 10 × at 4 ° C. in gas supersaturated water prepared using ultrapure water at 4 ° C. A double concentrated culture solution (10 × RPMI1640) (10 × culture solution) was added to prepare 1 × saline, 1 × phosphate buffer and 1 × RPMI1640. Immediately after the production, sealing was carried out, and a part was heated to 37 ° C., and then the aqueous solution was brought to 25 ° C., and the amount of gas generated was measured.
As a result, when gas supersaturated water was directly prepared using saline and PBS (phosphate buffer solution), no reduction in gas generation was observed compared to ultrapure water (see FIG. 11).
In addition, when a 10-fold concentrated solvent and gas supersaturated water prepared using ultrapure water were mixed and diluted to 1-fold concentration, the gas generation amount was reduced by 20-30% (see FIG. 12). In FIG. 12, “ultra pure water” represents the amount of gas supersaturated water produced at 4 ° C. using ultra pure water as a liquid and air as a gas, and “10 × saline” is: Represents the amount of physiological saline gas generated by diluting 10-fold concentrated saline with “ultra-pure water”. “10 × phosphate buffer” refers to 10-fold concentrated PBS (+) Represents the amount of gas generated in PBS (+) diluted 1-fold with “water”, “10 × RPMI1640” is the RPMI1640 medium diluted 10-fold in 10-fold concentrated RPMI1640 medium with “ultra-pure water” Represents the amount of gas generated.
An isotonic solution created by directly mixing a supersaturated amount of gas is compared with an isotonic solution created by once creating gas supersaturated water using ultrapure water and diluting with the gas supersaturated water. In addition, it was shown that the amount of gas generated increases and the amount of microbubbles generated increases.

Example 2
[Ultrasonic irradiation]
An example of collapse of microbubbles by ultrasonic waves will be shown.
FIG. 13 is a photograph of the gas supersaturated water A before and after ultrasonic irradiation, where (a) is before irradiation and (b) is after irradiation. In the figure, an ultrasonic bath is indicated by reference numeral 40.
In a beaker (300 mL), gas supersaturated water A prepared according to the method of Example 1 using ultrapure water as a liquid and nitrogen as a gas was placed.
As the ultrasonic bath 40, an ultrasonic bath using a 40 kHz bolt-tightened Langevin type vibrator (tank size: 240 × 140 × 150 mm) was used. The bath was filled with water, and the beaker and the beaker were immersed for about 1 to 2 seconds in the water in the bathtub irradiated with ultrasonic waves at an output of 100 W. As a result, microbubbles were generated as shown in FIG.

Example 3
[Examination of contrast ability]
In order to examine the imaging ability of gas supersaturated water, observation was performed using an ultrasonic imaging apparatus (Ultra diagnostic apparatus Sonovista MSC1585, probe 7.5 MHz manufactured by Mochida Siemens).
Specifically, a silicon tube tube was connected to a pump, and gas supersaturated water was flowed in the silicon tube (flow rate 74 ml / min). Ultrasonic waves were irradiated from the outside of the silicon tube (50kHz, 100W) to generate microbubbles. Immediately downstream (25 cm downstream) of the ultrasonic irradiation site, an imaging was confirmed using an ultrasonic imaging apparatus (Ultra diagnostic apparatus Sonovista MSC1585 manufactured by Mochida Siemens).
1) Examination of degree of supersaturation of air Gas supersaturated water with a known degree of supersaturation was prepared according to Example 1 using pure water (ultra pure water) as a liquid and air as a gas.
The degree of supersaturation is represented by the ratio of the amount of saturated solution to water at the same temperature and pressure (in addition, since the experiment was performed at room temperature: 20 ° C. and 1 atm, it is represented by the ratio to the amount of saturated solution at 25 ° C. and 1 atm. ing).
Gaseous supersaturated water having various degrees of supersaturation was prepared by diluting gaseous supersaturated water with a known supersaturation degree with saturated water. Create supersaturated water (supersaturated gas: air) with supersaturation levels of 1, 1.18, 1.38, 1.80, 2.41, 2.96, flow through the silicon tube, irradiate with ultrasound, and an ultrasound contrast device (Mochida Siemens) The maximum luminance was measured using an ultrasonic diagnostic apparatus, Sonovista MSC1585). As a result, the maximum brightness increased as the amount of air supersaturation increased, and the responsiveness to bubbled ultrasonic waves increased (FIG. 14).
Furthermore, 18 gas supersaturated water (supersaturated gas: air) having different supersaturation levels from 1 to 2.5 was prepared. The produced gas supersaturated water was flowed in a silicon tube, irradiated with ultrasonic waves, and the maximum luminance was measured using an ultrasonic contrast apparatus (Ultra diagnostic apparatus Sonovista MSC1585 manufactured by Mochida Siemens). As a result, the brightness in the silicon tube increased according to the degree of supersaturation of the gas supersaturated water (FIG. 15). In the case of air supersaturation, the contrast of the tube cross-sectional shape was confirmed at a supersaturation degree of 1.5 or more (Table 1 and FIG. 16).
2) Examination of supersaturation degree of oxygen, carbon dioxide and nitrogen According to Example 1, pure water (ultra pure water) is used as a liquid and oxygen, carbon dioxide or nitrogen is used as a gas. Created. Regarding nitrogen, gas supersaturated water having a high degree of supersaturation was prepared using a separate pressurized tank. The produced gas supersaturated water was flowed in a silicon tube, irradiated with ultrasonic waves, and the maximum luminance was measured using an ultrasonic contrast apparatus (Ultra diagnostic apparatus Sonovista MSC1585 manufactured by Mochida Siemens). As a result, in the case of oxygen and carbon dioxide, the contrast of the tube cross section was confirmed at a supersaturation level of 1.1 or higher, and in the case of nitrogen, the contrast of the tube cross section was confirmed at a supersaturation level of 1.5 or higher (see Table 1, FIGS. 17 and 16). Regarding air, it has been confirmed from 1) that a supersaturation level of 1.5 or higher is required for contrast imaging.
In addition, since the maximum luminance varies when the degree of supersaturation exceeds 4, it was confirmed that a degree of supersaturation of 4 or less is preferable for stable imaging (see FIG. 17).

3) Effect of gas supersaturated water viscosity on contrast ability When gas supersaturated water was injected into blood, it was considered that shearing force increased due to the effect of blood viscosity, making it difficult to control bubble formation. Therefore, it was investigated whether gas supersaturated water was injected or flowed into an aqueous solution having a viscosity comparable to that of blood, and whether or not it had a contrast ability. A silicon tube was connected to the pump, and a 40 vol% glycerin aqueous solution having a viscosity similar to that of blood was flowed into the silicon tube (flow rate: 74 ml / min). Gaseous supersaturated water was injected into the tube with a syringe, and ultrasonic waves were irradiated from the outside of the silicon tube tube 45 cm downstream (50 kHz, 100 W) to generate microbubbles. Immediately downstream (25 cm downstream) of the ultrasonic irradiation site, an imaging was confirmed using an ultrasonic imaging apparatus (Ultra diagnostic apparatus Sonovista MSC1585 manufactured by Mochida Siemens). As a result, even when injected into the same viscosity as blood, it was confirmed that the gas supersaturated water generates microbubbles by ultrasonic irradiation and enables imaging of the cross-sectional shape of the tube (FIG. 19 and FIG. 19). 18).
4) Examination of position of administration of gas supersaturated water and ultrasonic irradiation It was examined that the gas supersaturated water administered into the bloodstream retains the imaging ability as it is without being diluted. The silicon tube was connected to a pump, and pure water saturated with air (ultra pure water) was allowed to flow through the silicon tube (flow rate: 74 ml / min). Gas supersaturated water was injected into the tube at 1, 2 and 10 ml / sec with a syringe, and ultrasonic waves were irradiated (50 kHz, 100 W) from the outside of the silicon tube tube 3000 mm downstream to generate microbubbles. Immediately downstream (25 cm downstream) of the ultrasonic irradiation site, an imaging was confirmed using an ultrasonic imaging apparatus (Ultra diagnostic apparatus Sonovista MSC1585 manufactured by Mochida Siemens).
As a result, it was confirmed that bubbles were generated downstream of 3000 mm and imaging was possible (see FIGS. 21 and 20). Further, the faster the injection speed, the clearer the cross-sectional shape of the tube could be contrasted (see FIG. 22).
Even when it is administered into the body at a site distant from the contrast location, the gas supersaturated water is considered to have sufficient contrast capability at the target location.
Example 4
[Examination of ultrasonic frequency]
Microbubbles were generated by irradiating supersaturated water with ultrasonic waves at 50 KHz or 1 MHz. As a result, microbubbles having a diameter of about 20 μm were generated when 50 KHz ultrasonic waves were irradiated, and a diameter of about 1 μm was generated when 1 MHz ultrasonic waves were irradiated (see FIG. 23).

Example 5
[Examination of indirect ultrasonic irradiation]
When irradiating a human body with ultrasonic waves, since the ultrasonic waves are applied from above the skin to the blood vessels under the skin tissue, the ultrasonic waves are indirectly applied to the blood vessels through the subcutaneous tissue.
Therefore, a hole was placed in the center of a 12 cm × 18 cm agar phantom (see FIG. 24), and an ultrasonic probe (Mochida Siemens ultrasonic diagnostic device Sonovista MSC1585) was contacted from the outside of the agar phantom and irradiated with ultrasonic waves. (See FIG. 24). In the case of ultrapure water, the fluid in the hole was not contrasted, but in the case of gas supersaturated water, the fluid in the hole was contrasted.

1 Ultrasonic vibrator 2 Filter 3 Injection tube 4 Tube container (syringe)
5 Movable pusher (plunger)
6 Gas supersaturated water 7 Ultrasonic absorber 10 Ultrasonic vibration control device 20 Lipid supply device A Gas supersaturated water X Gas supersaturated water production device 40 Ultrasonic bath 51 Pressurization unit 52 Gas supply unit 53 Gas-liquid mixing unit 54 Gas separation 55 Depressurization part 56 Flow path 57 Discharge part 58 Gas removal part 61 Pump 63 Inlet part

Claims (8)

An ultrasonic contrast agent that vibrates or flows gas supersaturated water in which a gas equal to or higher than the saturated dissolution amount is dissolved so as to cause a pressure drop, generates bubbles in the gas supersaturated water by the pressure drop, and includes bubbles from the gas supersaturated water A bubble generating device for generating
An ultrasonic contrast medium injection device for injecting an ultrasonic contrast medium containing the bubbles into a living body.   The ultrasonic contrast agent injection device according to claim 1, wherein the bubble generating device includes an ultrasonic transducer that ultrasonically vibrates the gas supersaturated water. The ultrasonic contrast agent injecting apparatus further includes a cylindrical container that stores the gas supersaturated water therein, a movable pusher that is inserted into the cylinder from one end of the cylindrical container, and an injection tube that communicates with the inside of the cylinder,
The ultrasonic contrast agent injection device according to claim 2, wherein the ultrasonic transducer vibrates ultrasonically the gaseous supersaturated water flowing through the injection tube.   The ultrasonic contrast agent injection device according to claim 3, further comprising an ultrasonic absorber provided between the ultrasonic transducer and the cylindrical container for suppressing ultrasonic vibration transmission to gas supersaturated water inside the cylinder.   The filter according to any one of claims 1 to 4, further comprising a filter having micropores through which the ultrasonic contrast agent passes, wherein the filter removes bubbles exceeding a predetermined size included in the ultrasonic contrast agent. The ultrasonic contrast agent injection device as described.   The ultrasonic contrast agent injection device according to claim 5, wherein a substance that forms a lipid bilayer film in air bubbles is applied to the micropores of the filter.   The injection device according to claim 5 or 6, wherein a diameter of the micropore of the filter is 1 µm or less.   The injection device according to any one of claims 1 to 7, further comprising a temperature control device that adjusts a temperature of the gas supersaturated water in the bubble generating device.