Iontophoresis device structure

Details Iontophoresis device structure Iontophoresis device structure

1999-09-27

2001-07-10

Bockelman, Mark (Department: 3762)

Surgery

Means for introducing or removing material from body for...

Infrared, visible light, ultraviolet, x-ray or electrical...

C607S152000

Reexamination Certificate

active

06259946

ABSTRACT:

TECHNICAL FIELD
The present invention relates to an iontophoresis device structure used for transdermal or transmucosal drug administration.
BACKGROUND ART
Much active research in recent years has been devoted to preparations for transdermal or transmucosal administration, because of the advantages of absorption of drugs through the skin or mucous membranes of mammals, particularly humans, as compared with oral administration, from the viewpoint of easier administration, maintenance of blood levels and the ability to avoid side effects of drugs in the alimentary tract. Iontophoresis is one area which has received much attention as an effective method for local administration which accelerates absorption of drugs through the skin or mucous membranes.
Iontophoresis is a type of method for accelerating physical absorption of drugs whereby a voltage is applied to the skin or mucous membrane to induce electrical migration of the drug, for administration of the drug through the skin or mucous membrane.
Iontophoresis apparatuses consist largely of a power source apparatus which generates a current, and an iontophoresis device structure which includes an electrode layer for attachment to the skin or mucous membrane. Normally, an iontophoresis device structure is separated into a donor electrode which includes the drug, and a reference electrode. The iontophoresis which delivers the drug through the skin or mucous membrane is accomplished by forming a single electrical circuit with the power source, the iontophoresis device structure and the body and running a current through this circuit for electrical driving.
Connection between the electrode layer of the iontophoresis device structure and the power source is achieved using a snap-type protruding terminal such as disclosed in Japanese Laid-open Patent Publication No. 504343 of 1991 or Japanese Laid-open Patent Publication No. 196644 of 1996.
A conventional iontophoresis device structure will now be explained with reference to the attached drawings.
FIG. 7
is a cross-sectional schematic view of a conventional iontophoresis device structure, and
FIG. 8
is a cross-sectional schematic view of another conventional iontophoresis device structure.
Here,
20
is the conventional iontophoresis device structure,
21
is a support formed into a cup shape,
22
is an electrolyte layer fitted into the concave part of the support
21
,
23
and
24
are snap-type protruding terminals,
25
is an electrode layer electrically connected to the protruding terminal
24
, and
26
is a separator laminated in a freely releasable manner on the rim around the opening of the concave part of the support
21
.
The method of electrification for the above-mentioned iontophoresis device structure having this construction will now be explained.
In the structure illustrated in
FIG. 7
, the flat section under the protruding terminal
23
is contacted with the electrolyte layer
22
for use as the electrode layer, and the protruding part is connected with an external power source for electrification.
In the structure illustrated in
FIG. 8
, the bottom surface of the protruding terminal
24
is contacted with a separately provided electrode layer
25
for electrical connection, and the protruding part is connected with an external electrode for electrification through the electrode layer
25
which has a wide area.
These conventional iontophoresis device structures have had the following problems, however. Specifically,
(1) An insertion hole must be formed for the protruding terminal in order to project its protruding part through the bottom of the concave part of the cup-shaped support and an anchoring ring called a collar must be fitted to anchor the protruding terminal, thus requiring more working steps and reducing productivity, complicating mass production and raising costs.
(2) Leakage of the electrolyte or solvent such as water in the electrolyte layer from the insertion hole impairs the quality and lowers product yields.
(3) Because a non-flexible convex terminal is used as the snap-type protruding terminal, when the area of the underside of the terminal is widened to increase the contact between the convex terminal and the electrolyte layer in the case of the structure shown in
FIG. 7
, the contouring is poorer upon attachment to the body, while conversely if the underside of the terminal is reduced, a current flows directly under the lower end of the terminal, resulting in greater danger of electrical irritation to the body and lower safety.
(4) When a separate electrode layer is provided as shown in
FIG. 8
, it is necessary to carry out an integrating step for the more complex convex terminal as well as for the electrode layer, and thus working efficiency is reduced, productivity is impeded, and costs are increased.
(5) Although some structures employ silver or silver chloride in an ABS resin as the material for the convex terminal, and other structures have nickel platings on zinc, when ABS resins are used the terminal must be formed to a prescribed thickness to provide strength for the convex terminal, and hence there is a limit to how thin the thickness of the lower end of the terminal can be made. Also, structures wherein zinc is covered with a nickel plating, etc., have the problem of elution of the zinc or nickel, etc., by the electrolyte reaction upon electrification, so that the safety is poorer.
(6) When the protruding terminal is connected with the external power source, excessive pressure on the protruding terminal may break the iontophoresis device structure and cause leakage of its contents, such as the electrolyte layer.
(7) Because the rim of the protruding terminal is round, the connector is prone to detachment during electrification by the external power source.
The present invention overcomes these problems by providing an iontophoresis device structure which has excellent contouring ability at its site of attachment, has very high safety, is of high quality with high product yields, and can be produced with fewer production steps to improve working efficiency and increase productivity to allow mass production at low cost.
DISCLOSURE OF THE INVENTION
In order to achieve the object stated above, the present invention has the following construction.
The iontophoresis device structure according to claim
1
of the invention has a construction provided with a cup-shaped support including a concave part, at least one electrification hole formed in the concave part, an electrode layer formed on the flat part of the rim of the concave part, and an electrolyte layer fitted into the concave part.
Since the electrode layer is anchored on the outside of the flat part of the rim around the concave part of the support in this construction, its production is more simple allowing notable improvement in working efficiency, increasing productivity and lowering the cost. In addition, the adhesion between the flat part of the rim and the electrode layer around the concave part can be markedly increased, to help prevent leakage of the solvent of the electrolyte layer, etc.
Here, the support serves to hold the electrolyte layer, and it may be any material with excellent workability, flexibility and suitable shape retention and water retention; as examples there may be mentioned chlorinated resins such as vinylidene chloride and vinyl chloride polymers, as well as olefin-based, ester-based, styrene-based, acrylic-based, amide-based, oxymethylene-based, phenylene sulfide-based, amidoimide-based, acrylonitrile-based, etherketone, ethersulfone, sulfone, etherimide, butadiene and isoprene high molecular polymers or their copolymers, though there is no restriction to these and it is only necessary that the material have the effect mentioned above. Materials which have been formed into films and worked, or molded products, may be used. The thickness is not particularly restricted, but a thickness of 5-250 &mgr;m is preferred for superior shape retention and flexibility.
The electrolyte layer is a conductive layer containing an electrolyte which supplies the

Affiliated with

Also associated with

Rating

Iontophoresis device structure does not yet have a rating. At this time, there are no reviews or comments for this patent.

If you have personal experience with Iontophoresis device structure, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Iontophoresis device structure will most certainly appreciate the feedback.

Rate now

Comments { 0 }

Profile ID: LFUS-PAI-O-2550649