Transdermal delivery patch

Abstract

A transdermal delivery patch includes: a matrix; a volatile component; and a plurality of microcapsules dispersed in the matrix. Each of the microcapsules has an enclosing wall enclosing the volatile component therein. A method for preparing the transdermal delivery patch includes: mixing a first gel, a second gel with a charge opposite to that of the first gel, and a volatile component so as to form microcapsules enclosing the volatile component, each of the microcapsules having an enclosing wall that is composed of the first and second gels; dispersing the microcapsules in a matrix so as to form a medicinal dressing; and coating the medicinal dressing on a backing substrate.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

Other features and advantages of the present invention will become apparent in the following detailed description of the preferred embodiment of this invention, with reference to the accompanying drawings, in which;

FIG. 1 is a fragmentary schematic cross-sectional view of the preferred embodiment of a transdermal delivery patch according to this invention;

FIG. 2 is a fragmentary enlarged cross-sectional view of the preferred embodiment;

FIG. 3 is a flow chart illustrating a method of the preferred embodiment for preparing the transdermal delivery patch shown in FIG. 1;

FIG. 4 is a flow chart illustrating consecutive steps for producing microcapsules included in the transdermal delivery patch shown in FIG. 1;

FIG. 5 is a plot showing dissolution rates of menthol for a traditional hydrophilic transdermal patch and a hydrophilic transdermal matrix patch of this invention at 25° C.;

FIG. 6 is a plot showing dissolution rates of methyl salicylate for a traditional hydrophilic transdermal patch and a hydrophilic transdermal matrix patch of this invention at 25° C.;

FIG. 7 is a plot showing dissolution rates of menthol for a traditional hydrophobic transdermal patch and a hydrophobic transdermal matrix patch of this invention at 25° C.;

is FIG. 8 is a plot showing dissolution rates of methyl salicylate for a traditional hydrophobic transdermal patch and a hydrophobic transdermal matrix patch of this invention at 25° C.;

FIG. 9 is a plot showing dissolution rates of menthol for a hydrophilic transdermal matrix patch of this invention at 25° C. and 37° C.;

FIG. 10 is a plot showing dissolution rates of methyl salicylate for a hydrophilic transdermal matrix patch of this invention at 25° C. and 37° C.;

FIG. 11 is a plot showing dissolution rates of menthol for a hydrophobic transdermal matrix patch of this invention at 25° C. and 37° C.; and

FIG. 12 is a plot showing dissolution rates of methyl salicylate for a hydrophobic transdermal matrix patch of this invention at 25° C. and 37° C.

Claims

1. A transdermal delivery patch comprising: a matrix;a volatile component; anda plurality of microcapsules dispersed in said matrix, each of said microcapsules having an enclosing wall enclosing said volatile component therein.

2. The transdermal delivery patch of claim 1, wherein each of said microcapsules has a granular size ranging from 10 to 30 μm.

3. The transdermal delivery patch of claim 2, wherein said enclosing wall is composed of acacia gel and gelatin.

4. The transdermal delivery patch of claim 1, wherein said volatile component is selected from the group consisting of menthol, methyl salicylate, and aromatic essential oil of a plant.

5. The transdermal delivery patch of claim 4, wherein said plant is selected from the group consisting of Rhizoma Zingiberis Recens, Fructus Foeniculi, and Flos Caryphylli.

6. The transdermal delivery patch of claim 1, further comprising a backing substrate, said matrix being bonded to said backing substrate.

7. The transdermal delivery patch of claim 1, wherein said matrix is made from a material containing at least one of sodium polyacrylate, potassium polyacrylate, ammonium polyacrylate, monoethanolamine polyacrylate, diethanolamine polyacrylate, triethanolamine polyacrylate, carboxylmethyl cellulose sodium, carboxyl methyl starch, Tragacanth, polyvinyl alcohol, polycaroboxyethylene, polyethylene pyrrolidone, polyacrylic acid, polyethylene glycol, acacia, hydroxypropyl cellulose, hydroxyethyl cellulose, hydroxymethyl cellulose, gelatin, and agar.

8. The transdermal delivery patch of claim 1, wherein said matrix is made from a material containing at least one of synthetic rubber, natural rubber, pine resin, and resin.

9. A method for preparing a transdermal delivery patch, comprising: mixing a first gel, a second gel with a charge opposite to that of the first gel, and a first volatile component so as to form microcapsules enclosing the first volatile component, each of the microcapsules having an enclosing wall that is composed of the first and second gels;dispersing the microcapsules in a matrix so as to form a medicinal dressing; andcoating the medicinal dressing on a backing substrate.

10. The method of claim 9, further comprising, during forming of the microcapsules, adding an alkali agent into the mixture of the first and second gels and the first volatile component to prevent aggregation of the microcapsules.

11. The method of claim 9, wherein the matrix is prepared by mixing an aqueous phase composition and an oil phase composition, the aqueous phase composition being made from a material containing at least one of Carbopol, polyvinyl alcohol and carboxylmethyl cellulose, the oil phase composition being made from a material containing a second volatile component and a solvent for dissolving the second volatile component.

12. The method of claim 9, wherein the matrix is prepared by mixing an aqueous phase composition and an oil phase composition, the aqueous phase composition being made from a material containing at least one of synthetic rubber, natural rubber, pine resin, and resin, the oil phase composition being made from a material containing a second volatile component and a solvent for dissolving the second volatile component.

13. The method of claim 9, wherein each of the microcapsules has a granular size ranging from 10 to 30 μm.

14. The method of claim 9, wherein the first gel is acacia gel, and the second gel is gelatin.

15. The method of claim 12, wherein the first volatile component is the same as the second volatile component, and is selected from the group consisting of menthol, methyl salicylate, and aromatic essential oil of a plant.

16. The method of claim 15, wherein the plant is selected from the group consisting of Rhizoma Zingiberis Recens, Fructus Foeniculi, and Flos Caryphylli.