WO2025205760A1 - Drug delivery device - Google Patents

Abstract

Provided is a drug delivery device with which it is possible to efficiently improve drug permeability and which can be easily arranged on a curved surface of epithelial tissue. This drug delivery device has a base material sheet extending in a first direction, a drug-containing part containing a drug, and a plurality of electrodes extending in a direction that intersects the first direction and is parallel to the base material sheet, the plurality of electrodes being arranged at intervals in the first direction.

Description

Drug Delivery Devices

The present invention relates to a drug delivery device.

Iontophoresis is a known technique for applying a voltage to the skin using electrodes, thereby delivering a drug placed between the electrode and the skin into the body through the skin. Patent Document 1, for example, discloses an iontophoresis device for transdermal or transmucosal drug delivery that combines pulse depolarized current with at least one of direct current and pulsed current.

International Publication No. 1999/000157

Conventional drug delivery devices such as those described in Patent Document 1 can improve drug permeability into the body through the skin or mucous membranes, but in recent years there has been a demand for technology that can efficiently improve drug permeability. Furthermore, the inventors' research has revealed that, depending on the shape and placement of the electrodes, it may be difficult to place a drug delivery device on a curved surface, such as the surface of an arm. The present invention has been made in response to the above-mentioned problems, and its purpose is to provide a drug delivery device that can efficiently improve drug permeability and is easy to place on the curved surface of epithelial tissue.

The drug delivery device according to the embodiment that can solve the above problems is as follows.
[1] A base sheet extending in a first direction;
a drug-containing portion containing a drug;
a plurality of electrodes extending in a direction intersecting the first direction and parallel to the base sheet;
A drug delivery device, wherein the plurality of electrodes are spaced apart from one another in the first direction.

As described above, by arranging the plurality of electrodes extending in a direction intersecting the first direction with a gap in the first direction, the opposing length of adjacent electrodes can be increased, thereby efficiently improving drug permeability. Furthermore, with the above configuration, when the drug delivery device is placed on epithelial tissue with the first direction oriented, for example, in the circumferential direction of the arm, the plurality of electrodes can be easily positioned along the curved surface of the epithelial tissue of the arm. The drug delivery device according to the embodiment is preferably any one of [2] to [15] below.
[2] A drug delivery device as described in [1], wherein each of the plurality of electrodes is linear.
[3] A drug delivery device as described in [1], wherein the shape of each of the multiple electrodes is wavy or zigzag.
[4] A drug delivery device described in any one of [1] to [3], further having a band extending in the first direction and fixed directly or indirectly to the base sheet.
[5] The drug delivery device described in [4], wherein the band comprises an elastic fabric.
[6] The drug delivery device is placed in epithelial tissue,
The device further includes a cover sheet having an outer edge positioned outside an outer edge of the base sheet, and the surface of the cover sheet that is closer to the epithelial tissue has an adhesive,
The drug delivery device according to any one of [1] to [5], wherein the band is fixed to a cover sheet.
[7] The drug delivery device is placed in epithelial tissue,
the device further includes a cover sheet having an outer edge positioned outside an outer edge of the base sheet and extending in the first direction, and the surface of the cover sheet that is closer to the epithelial tissue has an adhesive;
A drug delivery device described in any one of [1] to [6], wherein the shortest distance from one end of the cover sheet to the other end in the first direction is at least two times and at most ten times the shortest distance from one end of the plurality of electrodes to the other end in the first direction.
[8] A drug delivery device described in any one of [1] to [7], further comprising a wiring portion connected to at least one of the plurality of electrodes, the wiring portion having a portion extending in the first direction.
[9] A drug delivery device described in any one of [1] to [8], wherein the extension directions of the multiple electrodes are each perpendicular to the first direction.
[10] The plurality of electrodes are
a plurality of first electrodes to which the same potential is applied;
a plurality of second electrodes to which the same potential is applied and which are applied with a potential different from the potentials to which the plurality of first electrodes are applied;
The drug delivery device according to any one of [1] to [9], wherein the plurality of first electrodes and the plurality of second electrodes are arranged alternately in the first direction.
[11] A drug delivery device described in any one of [1] to [10], wherein the drug-containing portion further contains moisture and a moisture-retaining substance, and the drug is ionized.
[12] The drug delivery device is placed in epithelial tissue,
The drug delivery device according to [10] or [11], wherein the drug-containing portion is arranged on the surface of the first electrodes that is closer to the epithelial tissue, or on the surface of the second electrodes that is closer to the epithelial tissue.
[13] A drug delivery device described in [10] or [11], wherein each of the plurality of first electrodes or each of the plurality of second electrodes includes the drug-containing portion.
[14] Further, the present invention has an electrolyte-containing portion containing water, a moisture-retaining substance, and an electrolyte,
The drug delivery device according to any one of [10] to [13], wherein the electrolyte-containing portion is disposed on a surface of the second electrodes that is closer to the epithelial tissue, or on a surface of the first electrodes that is closer to the epithelial tissue.
[15] Further, a power supply unit;
The drug delivery device according to any one of [1] to [14], further comprising a control unit that controls the flow of electricity from the power supply unit.

The present invention provides a drug delivery device that can efficiently improve drug permeability and is easy to place on the curved surface of epithelial tissue.

FIG. 1 is a diagram showing a basic structure of a drug delivery device according to an embodiment placed in epithelial tissue. FIG. 2 is a plan view of the drug delivery device according to the embodiment. FIG. 3 is a cross-sectional view taken along line III-III of FIG. 4 is a plan view showing the surfaces of the electrodes of the drug delivery device according to the embodiment of FIG. 2 that are closer to the epithelial tissue. 5 is a plan view showing a surface of a modified example of the electrodes of the drug delivery device according to the embodiment of FIG. 2 that is closer to the epithelial tissue. FIG. 6 is a cross-sectional view of a modified example of the drug delivery device according to the embodiment of FIG. 2 taken along line III-III. FIG. 7 is a plan view of an embodiment of a drug delivery device having a band. FIG. 8 is a cross-sectional view taken along line VIII-VIII in FIG. FIG. 9 is a plan view of an embodiment of a drug delivery device having multiple bands.

The present invention will be described in more detail below based on the following embodiments, but the present invention is not limited to these embodiments and can of course be implemented with appropriate modifications within the scope of the intent described above and below, all of which are encompassed within the technical scope of the present invention. For convenience, component reference numbers may be omitted from the drawings; in such cases, reference should be made to the specification or other drawings. The dimensions of the various components in the drawings may differ from their actual dimensions, as priority is given to aiding understanding of the features of the present invention.

The drug delivery device according to this embodiment has a base sheet extending in a first direction, a drug-containing portion containing a drug, and multiple electrodes extending in a direction intersecting the first direction and parallel to the base sheet, with the multiple electrodes being spaced apart in the first direction. By arranging the multiple electrodes extending in a direction intersecting the first direction with spaces in the first direction as described above, the opposing length of adjacent electrodes can be increased, thereby efficiently improving drug permeability. Furthermore, with this configuration, when the drug delivery device is placed on epithelial tissue with the first direction oriented, for example, to the circumferential direction of the arm, the multiple electrodes are more likely to be positioned along the curved surface of the epithelial tissue of the arm.

The basic configuration of a drug delivery device according to an embodiment will be described below with reference to the schematic diagram in Figure 1. As shown in Figure 1, drug delivery device 91 includes a drug-containing portion 20 containing a drug and multiple electrodes 10. Drug delivery device 91 preferably includes a power supply portion 50, a control portion 60 that controls the flow of electricity from power supply portion 50, and a wiring portion 70 that electrically connects each electrode to power supply portion 50. For example, a voltage can be applied to the multiple electrodes 10 from power supply portion 50 via wiring portion 70 under the control of control portion 60. When a voltage is applied to these electrodes, the drug can be delivered from drug-containing portion 20 into epithelial tissue 90, for example, along the direction of the arrow in Figure 1.

The drug delivery device according to the embodiment will be described in further detail below with reference to Figures 2 to 9. Figure 2 is a plan view of the drug delivery device according to the embodiment. Figure 3 is a cross-sectional view taken along III-III of Figure 2. Figure 4 is a plan view showing the surfaces of multiple electrodes in the drug delivery device according to the embodiment of Figure 2 that are closer to the epithelial tissue. Figure 5 is a plan view showing the surfaces of multiple electrodes in a modified version of the drug delivery device according to the embodiment of Figure 2 that are closer to the epithelial tissue. Figure 6 is a cross-sectional view taken along III-III of a modified version of the drug delivery device according to the embodiment of Figure 2. Figure 7 is a plan view of a drug delivery device according to an embodiment having a band. Figure 8 is a cross-sectional view taken along VIII-VIII of Figure 7. Figure 9 is a plan view of a drug delivery device according to an embodiment having multiple bands.

As shown in Figures 2, 3, and 4, the drug delivery device 91 according to this embodiment has a base sheet 40 extending in a first direction 40D, a drug-containing portion 20 containing a drug, and a plurality of electrodes 10 extending in a direction intersecting the first direction 40D and parallel to the base sheet 40. The plurality of electrodes 10 are each spaced apart in the first direction 40D.

By arranging multiple electrodes 10 extending in a direction intersecting the first direction 40D at intervals in the first direction 40D, the opposing length 10L between adjacent electrodes can be increased, thereby efficiently improving the permeability of the drug from the drug-containing portion 20.

A direction intersecting the first direction 40D means a direction that forms an angle with the first direction 40D of greater than 0 degrees. By extending the multiple electrodes 10 in a direction intersecting the first direction 40D, when the drug delivery device 91 is placed on the epithelial tissue 90 so that the first direction 40D is, for example, the circumferential direction of the arm, the multiple electrodes 10 are more likely to be positioned along the curved surface of the epithelial tissue 90 of the arm.

It is preferable that the extension direction 10D of the multiple electrodes 10 is perpendicular to the first direction 40D. This perpendicularity includes an error of 10 degrees or less. Specifically, the angle formed between the extension direction 10D of the multiple electrodes 10 and the first direction 40D is preferably 80 degrees or more and 100 degrees or less, more preferably 85 degrees or more and 95 degrees or less, and most preferably 90 degrees. The angle formed between the extension direction 10D of the multiple electrodes 10 and the first direction 40D may be 45 degrees or more and 135 degrees or less, or may be 60 degrees or more and 120 degrees or less. Furthermore, the extension directions 10D of the multiple electrodes 10 may be different directions, but are preferably the same direction.

The direction parallel to the base sheet 40 means a direction along at least one of the main surfaces of the base sheet 40. By having the multiple electrodes 10 extend in a direction parallel to the base sheet 40, the thickness of the drug delivery device 91 can be reduced. This parallelism also includes an error of 10 degrees or less. Specifically, the angle between the extension direction 10D of the multiple electrodes 10 and the main surface of the base sheet 40 is preferably 10 degrees or less, more preferably 5 degrees or less, and most preferably 0 degrees.

As shown in Figures 2, 3, and 4, the multiple electrodes 10 preferably include multiple first electrodes 1 that are applied with the same potential and multiple second electrodes 2 that are applied with the same potential but different from the potential applied to the multiple first electrodes 1. In this specification and claims, "different potentials" means that there is a difference in potential applied to the two electrodes. When a potential different from that of the first electrodes 1 is applied to the second electrode 2, a voltage can be applied to both electrodes. "Same potential" means that there is no difference in potential applied to the two electrodes. However, slight differences in potential caused by differences in wiring length, etc., are considered to be no difference in potential. For example, by applying a voltage so that the multiple first electrodes 1 are positive and the multiple second electrodes 2 are negative, the potential applied to the multiple first electrodes 1 will be different from the potential applied to the multiple second electrodes 2. Applying a voltage to the multiple first electrodes 1 and the multiple second electrodes 2 in this manner allows a drug to be delivered into the body. Note that it is not necessary to apply a voltage to all of the multiple electrodes 10; voltage may be applied to only some of the multiple electrodes 10.

As shown in FIG. 2, it is preferable that the multiple first electrodes 1 are connected in parallel by wiring sections 70. This makes it easier to apply the same potential to the multiple first electrodes 1. Furthermore, it is preferable that the multiple second electrodes 2 are connected in parallel by wiring sections 70. This makes it easier to apply the same potential to the multiple second electrodes 2.

As shown in Figures 2, 3, and 4, it is preferable that the multiple first electrodes 1 and the multiple second electrodes 2 are arranged alternately in the first direction 40D. This makes it easier to deliver drugs between adjacent electrodes.

As shown in Figure 4, the width of the gap between the first electrode 1 and the second electrode 2 is preferably smaller than the width of the first electrode 1 and smaller than the width of the second electrode 2. This makes it easier to deliver drugs between the electrodes.

Although not shown, the width of the gap between the first electrode 1 and the second electrode 2 is preferably larger than the width of the first electrode 1 and larger than the width of the second electrode 2. This reduces the effect of fluctuations in the gap width even when the base sheet 40 stretches in the first direction 40D.

As shown in Figure 4, it is preferable that each of the multiple electrodes 10 is linear. This linear shape makes it easier to wrap the drug delivery device 91 around epithelial tissue 90 on the arm, etc.

As shown in Figure 5, the shape of each of the multiple electrodes 10 is preferably wavy or zigzag. The wavy or zigzag shape allows the opposing length of adjacent electrodes to be increased, thereby more efficiently improving the permeability of the drug from the drug-containing portion 20. In Figures 2, 4, and 5, the outer edges of the multiple electrodes 10 each have multiple corners, but at least one corner may be rounded.

As shown in Figures 4 and 5, it is preferable that the multiple electrodes 10 are arranged at regular intervals in the first direction 40D. This reduces the difference in drug delivery amount between the electrodes.

As shown in FIG. 1, the drug delivery device 91 is preferably placed in the epithelial tissue 90. The drug delivery device 91 can deliver drugs from above the epithelial tissue 90 by applying a voltage to the electrodes while placed in the epithelial tissue 90. This makes the drug delivery device 91 suitable for use in so-called iontophoresis. The drug delivery device 91 is preferably configured to deliver drugs to body tissues other than the epithelial tissue 90 by completely passing through the epithelial tissue 90, but may also be configured to deliver drugs so that at least a portion of the drug remains in the epithelial tissue 90. In this case, the drug can be applied to the epithelial tissue 90.

The epithelial tissue 90 on which the drug delivery device 91 is placed is a cell layer that covers the surface of the body, the surface of a body cavity, or the surface of the lumen of an organ. The epithelial tissue 90 is preferably skin or mucosa, and more preferably skin. Skin or mucosa makes it easier to attach the drug delivery device 91 to a living body. Specifically, the drug delivery device 91 is preferably attached to the epithelial tissue of the arm, hand, leg, foot, back, abdomen, chest, face, head, or mouth, and more preferably attached to the curved surface of these epithelial tissues. Furthermore, the drug delivery device 91 is preferably configured to allow the drug to pass through at least the tight junctions of the epithelial tissue 90. The degree of penetration of the drug into the epithelial tissue 90 can be adjusted, for example, by controlling the voltage.

The drug delivery device 91 is preferably attached to the epithelial tissue 90 by being stuck, wrapped around, adsorbed, or left in place on the epithelial tissue 90, and more preferably attached to the epithelial tissue 90 by being stuck or wrapped around. Examples of attachment include sticking with an adhesive, which will be described later. Examples of wrapping include wrapping with a band, which will be described later. Examples of adsorption include adsorption with a porous sheet, which will be described later. Examples of placement include placement with a medical clip. The drug delivery device 91 is preferably placed on the epithelial tissue 90 of humans, but may also be placed on the epithelial tissue of animals other than humans, such as dogs, cats, horses, and cows.

The drug-containing section 20 contains a drug. The drug is preferably a pharmaceutical. A pharmaceutical is a drug used for the diagnosis, treatment, or prevention of a disease. The pharmaceutical preferably includes, for example, an anti-inflammatory agent, an antipyretic, an anti-inflammatory, an analgesic, an antibiotic, a local anesthetic, an anti-allergic agent, an anti-Alzheimer's agent, an anti-Parkinson's disease agent, a psychotropic agent, an anti-rheumatic agent, a smoking cessation aid, a circulatory agent, or a combination thereof. The pharmaceutical may also include a low-molecular-weight ionic compound, a peptide, a protein, an oligonucleotide, an antibody drug, a nucleic acid drug, or a combination thereof.

The molecular weight of the drug is preferably 100 or more and 1,000,000 or less, more preferably 500 or more and 50,000 or less, even more preferably 700 or more and 15,000 or less, and particularly preferably 1,000 or more and 8,000 or less. A drug with a molecular weight of 8,000 or less allows the drug to easily permeate the epithelial tissue 90.

It is preferable that the drug-containing portion 20 is adjacent to at least one of the multiple electrodes 10. This makes it easier for the drug to be delivered from the drug-containing portion 20 when a voltage is applied.

As shown in Figure 3, the drug-containing portion 20 is preferably arranged on surface 1E (hereinafter may be simply referred to as surface 1E) of the multiple first electrodes 1, which is closer to the epithelial tissue 90. In particular, when the multiple first electrodes 1 are anodes and the drug in the drug-containing portion 20 is positively charged, if the drug-containing portion 20 is arranged on surface 1E, the drug is thought to be more easily delivered into the epithelial tissue 90 due to the electrical repulsion between the drug and the cathode and the electroosmotic flow from the anode to the cathode. Furthermore, when the drug delivery device 91 has multiple drug-containing portions 20, it is preferable that each drug-containing portion 20 is arranged on surface 1E of the first electrode 1, which is closer to the epithelial tissue 90, as shown in Figure 3.

Although not shown, the drug-containing portions 20 are preferably arranged on the surface 2E (hereinafter sometimes simply referred to as surface 2E) of the multiple second electrodes 2 that is closer to the epithelial tissue 90. In particular, when the multiple second electrodes 2 are cathodes and the drug in the drug-containing portion 20 is negatively charged, if the drug-containing portion 20 is arranged on surface 2E, the drug will be more easily delivered into the epithelial tissue 90 due to the electrical repulsion between the drug and the cathode. Furthermore, when the drug delivery device 91 has multiple drug-containing portions 20, it is preferable that each drug-containing portion 20 is arranged on the surface 2E of each second electrode 2 that is closer to the epithelial tissue 90.

In the above example, a configuration in which multiple first electrodes 1 are anodes and multiple second electrodes 2 are cathodes was described, but multiple first electrodes 1 may also be cathodes and multiple second electrodes 2 may also be anodes. Furthermore, for example, the anode and cathode may be switched by changing the direction of the current at predetermined intervals.

The drug delivery device 91 may have multiple drug-containing portions 20. Some of the multiple drug-containing portions 20 may be arranged on surfaces 1E of the multiple first electrodes 1 that are closer to the epithelial tissue 90, and other drug-containing portions 20 may be arranged on surfaces 2E of the multiple second electrodes 2 that are closer to the epithelial tissue 90. When drug-containing portions 20 are arranged on surfaces 1E and 2E in this manner, it is preferable to change the direction of the current at predetermined intervals to switch between the anode and cathode, as described above.

The drug-containing portion 20 preferably further contains water and a moisture-retaining substance, and the drug is ionized. This makes it easier for the drug to be delivered into the epithelial tissue 90 when a voltage is applied.

The moisture-retaining material preferably includes a fabric, a paper sheet, a porous membrane, a hydrogel, or a combination thereof, more preferably includes a fabric, a hydrogel, or a combination thereof, and even more preferably includes a hydrogel.

The fabric preferably includes nonwoven fabric, woven fabric, knitted fabric, or a laminate thereof, and more preferably includes knitted fabric. The fabric preferably includes cotton, linen, silk, cellulose, cellulose derivatives, synthetic fibers, or combinations thereof. The synthetic fibers preferably include polyester resin, polyolefin resin, polyurethane resin, fluororesin, silicone resin, or combinations thereof. The paper sheet preferably includes pulp.

The porous membrane has air bubbles, and preferably has interconnected, open cells. The porous membrane preferably contains a fluororesin, polyolefin resin, polyester resin, silicone resin, cellulose, a cellulose derivative, or a mixture thereof. Examples of methods for forming air bubbles include dissolving a gas in a resin under high pressure and then reducing the pressure to form air bubbles; mixing a foaming agent into the resin and causing thermal decomposition or a chemical reaction to form air bubbles; mixing a filler into the resin and stretching the resin to form air bubbles at the interface between the resin and the filler; and mixing a bubble-forming agent into the resin and then eluting the bubble-forming agent with warm water or the like to form air bubbles. The fluororesin preferably contains polytetrafluoroethylene. The polyolefin resin preferably contains polyethylene, polypropylene, or a mixture thereof. The polyester resin preferably contains polyethylene terephthalate. The silicone resin preferably contains polydimethylsiloxane. The cellulose derivative preferably contains hydroxyethyl cellulose, hydroxypropyl cellulose, or a mixture thereof.

The hydrogel preferably contains a water-soluble polymer. The water-soluble polymer preferably has a crosslinked structure, a hydrophobic group, a crystalline structure, or a combination of these, and more preferably has a crosslinked structure. This makes the water-soluble polymer more likely to function as a gel. In particular, the crosslinked structure improves the shape retention of the hydrogel. The crosslinked structure of the water-soluble polymer may be formed using, for example, a polyvalent metal compound, a sequestering agent, a pH adjuster, or a combination of these.

The water-soluble polymer preferably includes a polysaccharide, a synthetic resin, or a mixture thereof, and more preferably includes a polysaccharide. The polysaccharide preferably includes gelatin, agar, agarose, dextran, carboxy starch, dextrin, methyl cellulose, ethyl cellulose, hydroxyethyl cellulose, carboxymethyl cellulose, chitosan, alginic acid, hyaluronic acid, a salt thereof, or a mixture thereof. The salt may be either a partially neutralized salt or a fully neutralized salt. The synthetic resin preferably includes polyvinyl alcohol, polyethylene oxide, polyvinyl methyl ether, polyvinyl ether-maleic anhydride copolymer, methoxyethylene-maleic anhydride copolymer, isobutylene-maleic anhydride copolymer, a silicone-containing copolymer, polyvinylpyrrolidone, polyacrylamide, a carboxyvinyl polymer, polyacrylic acid, a salt thereof, or a mixture thereof. The salt may be either a partially neutralized salt or a fully neutralized salt. The silicone-containing copolymer preferably has a siloxane structure, an ether structure, an ester structure, or both.

The drug-containing portion 20 may contain additives other than the drug, water, and moisture-retaining substance. The additives may include crosslinking agents, electrolytes, pH adjusters, fillers, adhesives, preservatives, moisturizers, antioxidants, colorants, fragrances, oils, UV absorbers, cooling agents, warming agents, transdermal absorption enhancers, conductive substances, or mixtures thereof.

The electrolyte preferably includes a salt. The salt preferably includes a halide. The halide preferably includes calcium chloride, potassium chloride, sodium chloride, calcium bromide, potassium bromide, sodium bromide, or a mixture thereof. The pH adjuster preferably includes acetic acid, phosphoric acid, citric acid, carbonic acid, or a salt thereof, or a mixture thereof.

The drug-containing portion 20 contains an adhesive, allowing it to be directly attached to the epithelial tissue 90. The drug-containing portion 20 contains a transdermal absorption enhancer, making it easier to deliver the drug into the epithelial tissue 90. The transdermal absorption enhancer preferably includes, for example, hydrophilic polyethers such as polyethylene glycol and polypropylene glycol; organic acid esters such as isopropyl myristate and isopropyl palmitate; fatty acids having 6 to 20 carbon atoms such as oleic acid, stearic acid, and palmitic acid; squalane; castor oil; anionic surfactants; cationic surfactants; amphoteric surfactants; or mixtures thereof. When the drug-containing portion 20 contains a conductive material, it can function as an electrode. The conductive material preferably includes conductive fibers, a conductive filler, or a combination thereof. The conductive filler preferably includes conductive particles.

In Figures 1, 2, etc., the outer edge of the drug-containing portion 20 has the same shape as the outer edge of the adjacent electrode, but it may have a different shape. For example, the outer edge of the drug-containing portion 20 may be located further outward than the outer edge of the adjacent electrode. In this case, the area of the surface of the drug-containing portion 20 closer to the epithelial tissue 90 is larger than that of the adjacent electrode, so the amount of drug that can be stored in the drug-containing portion 20 can be increased. Furthermore, irritation to the epithelial tissue 90 when voltage is applied can be reduced. The shape of the outer edge of the drug-containing portion 20 may be similar to the shape of the outer edge of the adjacent electrode, but it does not have to be similar.

As shown in Figure 3, the drug delivery device 91 preferably further includes an electrolyte-containing portion 30 containing water, a moisture-retaining substance, and electrolytes. The water and electrolytes in the electrolyte-containing portion 30 can reduce skin resistance and power consumption. The electrolyte-containing portion 30 preferably does not contain any drugs.

The moisture-retaining substance preferably includes a fabric, a paper sheet, a porous membrane, a hydrogel, or a combination thereof, more preferably a fabric, a hydrogel, or a combination thereof, and even more preferably a hydrogel. For details, please refer to the description of the moisture-retaining substance of the drug-containing portion 20. Note that the electrolyte-containing portion 30 preferably includes the same moisture-retaining substance as the drug-containing portion 20, but does not have to include the same moisture-retaining substance.

The electrolyte preferably includes a salt. The salt preferably includes a halide. The halide preferably includes calcium chloride, potassium chloride, sodium chloride, calcium bromide, potassium bromide, sodium bromide, or a mixture thereof.

The electrolyte-containing portion 30 may contain additives other than water, a moisture-retaining substance, and electrolytes. The additives may include a pH adjuster, a filler, an adhesive, a preservative, a moisturizer, an antioxidant, a colorant, a fragrance, an oil, an ultraviolet absorber, a cooling agent, a warming agent, a conductive substance, or a mixture thereof. When the electrolyte-containing portion 30 contains an adhesive, the electrolyte-containing portion 30 can be directly attached to the epithelial tissue 90. When the electrolyte-containing portion 30 contains a conductive substance, the electrolyte-containing portion 30 can function as an electrode. The conductive substance preferably contains conductive fibers, a conductive filler, or a combination thereof. The conductive filler preferably contains conductive particles.

As shown in FIG. 3, the electrolyte-containing portions 30 are preferably arranged on the surfaces 2E of the multiple second electrodes 2 that are closer to the epithelial tissue 90. In particular, when the drug-containing portions 20 are arranged on the surfaces 1E of the multiple first electrodes 1 that are closer to the epithelial tissue 90, the drug is more easily delivered into the epithelial tissue 90 by having the electrolyte-containing portions 30 arranged on the surfaces 2E of the multiple second electrodes 2. Furthermore, when the drug delivery device 91 has multiple electrolyte-containing portions 30, it is preferable that each electrolyte-containing portion 30 is arranged on the surface 2E of each second electrode 2 that is closer to the epithelial tissue 90, as shown in FIG. 3.

Although not shown, the electrolyte-containing portion 30 is preferably arranged on the surface 1E of the multiple first electrodes 1 that is closer to the epithelial tissue 90. In particular, when the drug-containing portion 20 is arranged on the surface 2E of the multiple second electrodes 2 that is closer to the epithelial tissue 90, the drug is more easily delivered into the epithelial tissue 90 by having the electrolyte-containing portion 30 arranged on the surface 1E of the multiple first electrodes 1. Furthermore, when the drug delivery device 91 has multiple electrolyte-containing portions 30, it is preferable that each electrolyte-containing portion 30 is arranged on the surface 1E of each first electrode 1 that is closer to the epithelial tissue 90.

In Figures 1, 2, etc., the outer edge of the electrolyte-containing portion 30 has the same shape as the outer edge of the adjacent electrode, but it may have a different shape. For example, the outer edge of the electrolyte-containing portion 30 may be located further outward than the outer edge of the adjacent electrode. In this case, the surface area of the electrolyte-containing portion 30 closer to the epithelial tissue 90 is larger than that of the adjacent electrode, so that stimulation of the epithelial tissue 90 when voltage is applied can be reduced. Furthermore, the shape of the outer edge of the electrolyte-containing portion 30 may be similar to the shape of the outer edge of the adjacent electrode, but it does not have to be similar.

Each electrode preferably contains a conductive material, more preferably consists of a conductive material. The conductive material preferably contains a metal, carbon, or a mixture thereof, more preferably contains a metal. The metal preferably contains gold, silver, silver halide, copper, platinum, zinc, lead, tin, titanium, aluminum, nickel, or an alloy thereof, more preferably contains silver, silver halide, or zinc, and even more preferably contains silver chloride or zinc. When the electrodes contain an electrochemically active metal, it is possible to more easily reduce pH changes, mainly caused by the electrolysis of water. For example, if the first electrode 1 contains zinc and the second electrode 2 contains silver chloride, it is possible to more easily reduce pH changes. Reducing pH changes can reduce skin irritation. The metal is preferably in the form of a plate, fiber, or particle, with plate-like shape being preferred. The carbon preferably contains carbon fiber, graphite, ketjen black, fullerene, carbon nanotube, carbon nanohorn, furnace black, or a mixture thereof. The carbon is preferably in the form of a plate, fiber, or particle, with plate-like shape being preferred. For example, the first electrode 1 may contain carbon and the second electrode 2 may contain silver chloride.

It is preferable that the drug-containing portion 20 or electrolyte-containing portion 30 be fixed to the surface of each electrode closest to the epithelial tissue 90. This makes it easier to pass electricity from the electrode to the drug-containing portion 20 or electrolyte-containing portion 30. Specifically, it is preferable that these be fixed with a conductive adhesive. Using a conductive adhesive can reduce power loss.

Although not shown, each of the multiple first electrodes 1 or each of the multiple second electrodes 2 may include a drug-containing portion 20. This allows the thickness of the drug delivery device 91 to be reduced. In this case, the multiple first electrodes 1 or multiple second electrodes 2 preferably contain a drug, a conductive substance, moisture, and a moisture-retaining substance. For example, the multiple first electrodes 1 or multiple second electrodes 2 may each be a conductive fiber to which a hydrogel containing a drug and moisture is attached, a hydrogel containing a drug, moisture, and a conductive filler, or a porous sheet containing a drug, moisture, and a conductive filler.

Although not shown, the multiple first electrodes 1 or the multiple second electrodes 2 may include an electrolyte-containing portion 30. This allows the thickness of the drug delivery device 91 to be reduced. In this case, the multiple first electrodes 1 or the multiple second electrodes 2 preferably contain a conductive material, water, an electrolyte, and a moisture-retaining material. For example, each of the multiple first electrodes 1 or each of the multiple second electrodes 2 may be a conductive fiber to which a hydrogel containing electrolyte and water is attached, a hydrogel containing electrolyte, water, and a conductive filler, or a porous sheet containing electrolyte, water, and a conductive filler.

As shown in Figures 2 and 3, the drug delivery device 91 has a base sheet 40 extending in a first direction 40D. Because the base sheet 40 extends in the first direction 40D, when the base sheet 40 is placed on the epithelial tissue 90 with the first direction 40D oriented in the circumferential direction of the arm, for example, the base sheet 40 is likely to curve along the circumferential direction of the arm. It is preferable that a plurality of electrodes 10 be arranged on the base sheet 40.

As shown in Figures 2 and 3, the drug delivery device 91 preferably further includes a power supply unit 50 and a control unit 60 that controls the flow of electricity from the power supply unit 50. The drug delivery device 91 preferably further includes a wiring unit 70 that is connected to at least one of the multiple electrodes 10. The drug delivery device 91 preferably further includes a cover sheet 41 that has an outer edge positioned outside the outer edge of the base sheet 40 and extends in the first direction 40D. Each part will be described in order below.

As shown in FIG. 3, the base sheet 40 preferably supports multiple electrodes 10 directly or indirectly. For example, it is preferable that each electrode be fixed to the surface of the base sheet 40 closer to the epithelial tissue 90 (hereinafter sometimes referred to as the "lower surface"). Furthermore, it is preferable that the power supply unit 50, the control unit 60, or both of these be fixed to the surface of the base sheet 40 farther from the epithelial tissue 90 (hereinafter sometimes referred to as the "upper surface"). This allows the base sheet 40 to support each electrode, power supply unit 50, and control unit 60. These are preferably fixed with a pressure-sensitive adhesive or adhesive, and are more preferably fixed with an adhesive. Furthermore, each electrode may be formed on the base sheet 40 by printing.

The base sheet 40 preferably contains an insulator, and more preferably consists of an insulator. This makes it easier to prevent electrical leakage. Furthermore, the base sheet 40 preferably supports the wiring section 70 directly or indirectly. At least a portion of the wiring section 70 may be fixed to the base sheet 40 with an adhesive or bonding agent, or may be formed on the base sheet 40 by printing.

The shape of the base sheet 40 in a plan view is preferably polygonal, elliptical, or dumbbell-shaped, more preferably polygonal, and even more preferably rectangular. The polygon may be rectangular, hexagonal, octagonal, or any of these rounded polygons.

As shown in FIG. 3, the drug delivery device 91 preferably further includes a shape-retaining member 40R that maintains the outer shape of the drug-containing portion 20. The shape-retaining member 40R preferably includes a first through-hole 40H in which the drug-containing portion 20 is disposed. This makes it easier to maintain the outer shape of the drug-containing portion 20. The shape-retaining member 40R preferably further includes a second through-hole 40I in which the electrolyte-containing portion 30 is disposed. This makes it easier to maintain the outer shape of the electrolyte-containing portion 30.

It is preferable that the shape-retaining member 40R is fixed to the base sheet 40. Specifically, it is preferable that the upper surface of the shape-retaining member 40R is fixed to the lower surface of the base sheet 40. These are preferably fixed with a pressure-sensitive adhesive or adhesive, and it is more preferable that they are fixed with an adhesive.

The shape of the first through hole 40H and the second through hole 40I in a plan view is preferably a convex polygon, a concave polygon, a circle, an ellipse, an arch, a wave, a zigzag, or a combination of these, and is more preferably a convex polygon, a wave, or a zigzag. The convex corners of a convex polygon may be rounded. The convex corners, concave corners, or both of the convex corners of a concave polygon may be rounded.

The shape-retaining member 40R preferably includes an insulator, and more preferably is made of an insulator. This makes it easier to prevent electrical leakage.

The shape-retaining member 40R is preferably sheet-shaped. The shape of the shape-retaining member 40R in a plan view is preferably polygonal, circular, elliptical, or dumbbell-shaped, more preferably polygonal, and even more preferably rectangular. The polygon may be a square, rectangle, hexagon, octagon, or any of these rounded polygons.

The drug delivery device 91 does not have to have a shape-retaining member 40R, and if it does not have a shape-retaining member 40R, the base sheet 40 may have the function of the shape-retaining member 40R. For example, although not shown, the base sheet 40 may have a first recess, in which a first electrode 1 and a drug-containing portion 20 are disposed. The base sheet 40 may further have a second recess, in which a second electrode 2 and an electrolyte-containing portion 30 are disposed. Alternatively, the first electrode 1 and electrolyte-containing portion 30 may be disposed in the first recess, and the second electrode 2 and drug-containing portion 20 may be disposed in the second recess.

The base sheet 40, the shape-retaining member 40R, or both preferably contain a resin sheet, a paper sheet, fabric, or a laminate of these, and more preferably contain a resin sheet. The resin sheet preferably contains a non-elastic material, an elastic material, or a mixture of these, and more preferably contains an elastic material. The inclusion of an elastic material improves the ability of the base sheet 40 to follow the expansion and contraction of the epithelial tissue 90. Examples of non-elastic materials include synthetic resins such as polyester resin, polyolefin resin, and polyamide resin. Examples of elastic resins include polyurethane resin, rubber, and elastomer. The resin sheet may also contain a porous sheet. For example, if the shape-retaining member 40R contains a porous sheet, it can be more easily adhered to the epithelial tissue 90. In this case, the porous sheet preferably has closed cells that are not connected to each other. The paper sheet preferably contains pulp.

The fabric preferably includes nonwoven fabric, woven fabric, knitted fabric, or a laminate thereof, and more preferably includes nonwoven fabric, woven fabric, or a laminate thereof. When the fabric includes nonwoven fabric or woven fabric, it becomes easier to prevent the epithelial cells from drying out. Preventing the epithelial cells from drying out is expected to improve drug permeability. On the other hand, when the fabric includes knitted fabric, the ability of the base sheet 40 or shape-retaining member 40R to follow the expansion and contraction of the epithelial tissue 90 is improved. It is preferable that the fibers of the fabric have resin on at least the surface, and it is more preferable that the fibers of the fabric are made of resin. This makes it easier for the insulating properties of the fabric to be exhibited.

The base sheet 40 preferably contains a material that is less elastic than the material of the shape-retaining member 40R, and more preferably is made of a material that is less elastic than the material of the shape-retaining member 40R. This makes it easier for the base sheet 40 to support each electrode.

The shape-retaining member 40R preferably contains a material that is more elastic than the material of the base sheet 40, and more preferably is made of a material that is more elastic than the material of the base sheet 40. This allows the shape-retaining member 40R to easily deform in response to the expansion and contraction of the epithelial tissue 90.

The surface of the cover sheet 41 closest to the epithelial tissue 90 preferably has an adhesive. In this case, it is preferable that this surface has an adhesive at least in a portion outside the outer edge of the base sheet 40, and it is more preferable that this surface has an adhesive in a portion outside and inside the outer edge of the base sheet 40. This allows the cover sheet 41 to adhesively fix electrodes, etc. to the surface of the epithelial tissue 90. Alternatively, this surface may have an adhesive in a portion outside the outer edge of the base sheet 40, and an adhesive in a portion inside the outer edge. This makes it easier to firmly fix the cover sheet 41 to the base sheet 40, etc.

As shown in Figure 3, the shortest distance L1 from one end 41A to the other end 41B of the cover sheet 41 in the first direction 40D is preferably at least two times and no more than ten times the shortest distance L2 from one end 10A to the other end 10B of the multiple electrodes 10 in the first direction 40D. A magnification of at least two times makes it easier to wrap the cover sheet 41 around epithelial tissue 90 of the arm, etc. On the other hand, a magnification of no more than ten times makes the cover sheet 41 easier to handle. The magnification is more preferably at least three times and no more than nine times.

As shown in FIG. 6 , the shortest distance from one end 41A of the cover sheet 41 to one end 40A of the base sheet 40 in the first direction 40D may be longer than the shortest distance from the other end 41B of the cover sheet 41 to the other end 40B of the base sheet 40. For example, the shortest distance from one end 41A to one end 40A in the first direction 40D may be at least two, four or eight times the shortest distance from the other end 41B to the other end 40B in the first direction 40D, or may be no more than 20, 15 or 10 times the shortest distance from the other end 41B to the other end 40B. This allows the cover sheet 41 to be wrapped around epithelial tissue 90 of the arm, etc., by cutting off the excess portion of the cover sheet 41 near one end 41A with scissors, or by wrapping the excess portion over the other end 41B, the cover sheet can be wrapped more securely around the arm, etc.

The power supply unit 50 preferably has a primary battery or a secondary battery. The primary battery is preferably a lithium battery, and more preferably a coin-type lithium battery. This reduces costs and is particularly suitable when the drug delivery device 91 is to be used once and then discarded. The power supply unit 50 may have multiple batteries, for example, two coin-type lithium batteries connected in series. In this case, the voltage is preferably 0.1 V or more and 6 V or less. The current density is preferably 0.01 mA/ ^cm2 or more and 0.4 mA/ ^cm2 or less.

The control unit 60 is a part that controls the supply of electricity from the power supply unit 50. The preferred form of electricity is DC electricity, pulse electricity, pulse depolarized electricity, or a combination of these, with pulse electricity being more preferred. DC electricity is a form in which a predetermined direct current is applied between the electrodes. Pulse electricity is a form in which a predetermined repetitive pulse is applied between the electrodes. Pulse depolarized electricity is a form in which a predetermined repetitive pulse is applied between the electrodes, and residual charge is forcibly discharged when the pulses stop.

The control unit 60 preferably has a DC output, a pulse output, a pulse depolarized output, or a circuit for executing these outputs, and more preferably has a circuit for executing pulse output. The control unit 60 may further have a processor and memory. For example, the control unit 60 may be configured so that the processor switches between DC output, pulse output, and pulse depolarized output in accordance with a program recorded in the memory. Examples of memory include an SSD, HDD, and ROM. The control unit 60 may also have a circuit capable of changing the direction of current. For example, the control unit 60 may be configured so that the processor changes the direction of current using the circuit in accordance with a program recorded in the memory. This allows for alternating switching between anode and cathode. For example, the control unit 60 may switch from a mode in which a voltage is applied so that the first electrode 1 is the anode and the second electrode 2 is the cathode to a mode in which a voltage is applied so that the first electrode 1 is the cathode and the second electrode 2 is the anode. If the first electrode 1, the second electrode 2, or both are active electrodes, switching the electrodes in this manner can regenerate consumed electrodes.

The pulse frequency of the pulse voltage is preferably 0.5 Hz or more and 50 Hz or less. This allows the drug delivery device 91 to increase the skin permeability of the drug while reducing irritation of the epithelial tissue 90 caused by the application of voltage. The pulse frequency of the pulse voltage is not limited to the above range and may be, for example, 0.5 Hz or more and 5,000 kHz or less, 0.5 Hz or more and 50 kHz or less, or 0.5 Hz or more and 5 kHz or less.

The pulse width is preferably between 10 ms and 1000 ms. The pulse width corresponds to the time during one cycle that the output is on. The pulse width is preferably between 40% and 60% of one cycle, and more preferably between 45% and 55%.

The waveform of the pulse voltage is preferably a square wave, triangular wave, sawtooth wave, or sine wave, and more preferably a square wave.

The control unit 60 preferably performs pulse output by controlling the voltage, but may also perform pulse output by controlling the current.

Each function in the control unit 60 may be implemented by, for example, a processor, an ASIC (Application Specific Integrated Circuit), a DSP (Digital Signal Processor), an FPGA (Field Programmable Gate Array), or a combination of these. The control unit 60 may also have a constant voltage diode or a constant current diode.

The wiring unit 70 allows each electrode to be electrically connected to the power supply unit 50. It is preferable that a control unit 60 is disposed between each electrode and the power supply unit 50. This allows the control unit 60 to control the flow of electricity to the electrodes.

As shown in Figure 2, it is preferable that the wiring portion 70 has a portion extending in the first direction 40D. By having the wiring portion 70 have a portion extending in the first direction 40D, it becomes easier to prevent excessive stretching of the base sheet 40 in the first direction 40D, and fluctuations in the inter-electrode distance between the multiple electrodes 10 can be reduced.

The wiring of the wiring section 70 is preferably in the form of a film or cable, and more preferably in the form of a film. Examples of film-shaped wiring include printed wiring produced by screen printing, etching, etc. Examples of cable-shaped wiring include metal wires coated with an insulating film.

The wiring of the wiring section 70 preferably contains metal, carbon, or a mixture of these, and more preferably contains metal. The metal preferably contains gold, silver, silver halide, copper, platinum, zinc, lead, tin, titanium, aluminum, nickel, or an alloy of these, and more preferably contains silver. The carbon preferably contains carbon fiber, graphite, ketjen black, fullerene, carbon nanotube, carbon nanohorn, furnace black, or a mixture of these. The wiring of the wiring section 70 may also contain an elastic material and a conductive filler. This makes the wiring section 70 more flexible. Examples of elastic materials include polyurethane resin and elastomer.

It is preferable that the power supply unit 50, control unit 60, and each electrode are connected in sequence by wires.

It is preferable that the drug delivery device 91 has an integrated structure in which all components are placed in the epithelial tissue 90, as shown in Figures 2 and 3.

As shown in Figures 7 and 8, the drug delivery device 91 preferably further includes a band 42 extending in the first direction 40D and fixed directly or indirectly to the base sheet 40. This makes it easier to wrap and attach the drug delivery device 91 around epithelial tissue 90 on the arm, etc.

The band 42 preferably includes a stretchable fabric. The stretchable fabric is preferably stretchable in at least the first direction 40D. This makes it easier to prevent excessive stretching of the base sheet 40 in the first direction 40D, and reduces fluctuations in the inter-electrode distance between the multiple electrodes 10. The stretchable fabric preferably includes a stretch bandage, a rubber sheet, a polyurethane nonwoven fabric, or a combination thereof.

The band 42 may have a connecting member 42C at at least one of its two end portions in the first direction 40D. Examples of the connecting member 42C include hooks, loops, hook-and-loop fasteners, buckles, buttons, snaps, and adhesive sheets. In Figure 7, the band 42 has a male hook-and-loop fastener at one end portion in the extension direction and a female hook-and-loop fastener at the other end portion in the extension direction as the connecting member 42C. By joining these, the two end portions can be connected. In Figures 7 and 8, the drug delivery device 91 has one band 42, but as shown in Figure 9, it may have two or more bands 42. In this case, it is preferable that the bands 42 are fixed to one end and the other end portion of the cover sheet 41 in the first direction 40D. Although not shown, the band 42 may be a cylindrical body with both widthwise end portions fixed.

As shown in Figures 7, 8, and 9, the band 42 is preferably fixed to the cover sheet 41. This allows the band 42 to be fixed to the base sheet 40 via the cover sheet 41. Alternatively, although not shown, the band 42 may be fixed directly to the base sheet 40.

This application claims the benefit of priority from Japanese Patent Application No. 2024-051372, filed March 27, 2024. The entire contents of the specification of Japanese Patent Application No. 2024-051372, filed March 27, 2024, are incorporated herein by reference.

1, 2 First electrode, second electrode 1E, 2E Surface closer to epithelial tissue 10 Multiple electrodes 10A One end 10B Other end 10D Extension direction 20 Drug-containing portion 30 Electrolyte-containing portion 40 Base sheet 40D First direction 40A One end 40B Other end 40R Shape-retaining member 40H First through-hole 40I Second through-hole 41 Cover sheet 41A One end 41B Other end 42 Band 50 Power supply unit 60 Control unit 70 Wiring unit 90 Epithelial tissue 91 Drug delivery device

Claims (15)

a base sheet extending in a first direction;
a drug-containing portion containing a drug;
a plurality of electrodes extending in a direction intersecting the first direction and parallel to the base sheet;
A drug delivery device, wherein the plurality of electrodes are spaced apart from one another in the first direction. The drug delivery device of claim 1, wherein each of the plurality of electrodes is linear. The drug delivery device of claim 1, wherein each of the multiple electrodes has a wavy or zigzag shape. The drug delivery device of claim 1 or 2, further comprising a band extending in the first direction and fixed directly or indirectly to the base sheet. The drug delivery device of claim 4, wherein the band comprises an elastic fabric. the drug delivery device is placed in epithelial tissue;
The device further includes a cover sheet having an outer edge positioned outside an outer edge of the base sheet, and the surface of the cover sheet that is closer to the epithelial tissue has an adhesive,
The drug delivery device of claim 4, wherein the band is fixed to the cover sheet. the drug delivery device is placed in epithelial tissue;
the device further includes a cover sheet having an outer edge positioned outside an outer edge of the base sheet and extending in the first direction, and the surface of the cover sheet that is closer to the epithelial tissue has an adhesive;
A drug delivery device as described in claim 1 or 2, wherein the shortest distance from one end to the other end of the cover sheet in the first direction is at least two times and not more than ten times the shortest distance from one end to the other end of the plurality of electrodes in the first direction. The drug delivery device of claim 1 or 2, further comprising a wiring portion connected to at least one of the plurality of electrodes, the wiring portion having a portion extending in the first direction. The drug delivery device of claim 1 or 2, wherein the extension directions of the multiple electrodes are each perpendicular to the first direction. The plurality of electrodes
a plurality of first electrodes to which the same potential is applied;
a plurality of second electrodes to which the same potential is applied and which are applied with a potential different from the potentials to which the plurality of first electrodes are applied;
The drug delivery device according to claim 1 or 2, wherein the plurality of first electrodes and the plurality of second electrodes are arranged alternately in the first direction. The drug delivery device of claim 1 or 2, wherein the drug-containing portion further contains water and a moisture-retaining substance, and the drug is ionized. the drug delivery device is placed in epithelial tissue;
The drug delivery device according to claim 10 , wherein the drug-containing portion is arranged on a surface of the first electrodes that is closer to the epithelial tissue or a surface of the second electrodes that is closer to the epithelial tissue. The drug delivery device described in claim 10, wherein each of the plurality of first electrodes or each of the plurality of second electrodes includes the drug-containing portion. Further, the electrolyte-containing portion includes water, a water-retaining substance, and an electrolyte,
The drug delivery device according to claim 12, wherein the electrolyte-containing portion is arranged on a surface of the second electrodes that is closer to the epithelial tissue or on a surface of the first electrodes that is closer to the epithelial tissue. Furthermore, the power supply unit,
The drug delivery device according to claim 1 or 2, further comprising a control unit that controls the supply of electricity from the power supply unit.