Surgery – Means for introducing or removing material from body for... – Infrared – visible light – ultraviolet – x-ray or electrical...
Patent
1994-10-20
1997-06-10
Bockelman, Mark
Surgery
Means for introducing or removing material from body for...
Infrared, visible light, ultraviolet, x-ray or electrical...
604290, 424449, A61N 130
Patent
active
056370849
DESCRIPTION:
BRIEF SUMMARY
BACKGROUND OF THE INVENTION
This application is a 371 of PCT/FI 93/00083 filed Mar. 10, 1993.
The present invention relates to an iontophoretic method for drug delivery and a device suitable for use in carrying out this method.
In the present method, an electric current is generated by creating Galvani potential differences across at least two different ion selective membranes via a salt concentration difference over the membranes and bringing one artion selective membrane and one cation selective membrane into contact with human or animal body either directly or indirectly. According to a feature of the invention at least one reservoir containing a salt solution is needed, the concentration of which differs from the salt concentration of the extracellular fluids in human or animal tissues. The method of the invention can be specially used with transdermal preparations but also with mucoadhesive preparations and implants. For simplicity, the description which follows will refer to devices which are transdermal preparations, but it is to be understood that the method and device may be adapted to apply to mucoadhesive preparations and implants.
DESCRIPTION OF THE BACKGROUND ART
Iontophoresis or iontophoretic therapy is the delivery into human or animal tissue of a drug by the use of an electric field or current. Reviews of methods, devices and drugs suitable for iontophoretic delivery are contained in e.g. Journal of Controlled Release Vol. 7, 1988, pp. 1-24, Drug Design and Delivery Vol. 4, 1989, pp. 1-12 and Journal of Pharmaceutical Sciences Vol. 78, 1989, No. 5, pp. 376-383. In addition to transdermal applications the methods have also been used in ophthalmologic therapy (A. K. Banga & Y. W. Chien, J. Controlled Release Vol. 7, 1988, pp. 1-24).
U.S. Pat. No. 4,722,726 discloses a device for iontophoretic delivery of active ingredients, where an ion selective membrane is used to only separate an electrode and a first chamber containing an electrolyte from a second chamber containing an active ingredient. An additional power source for the generetion of electric current is needed.
For the generation of electric current some kind of a battery is always needed, and current is introduced into the tissues of the body via wires and electrodes. The electric circuit is closed through the body of a patient after attaching a device on the surface of the body or by the implantation of a device. The flux of a drug is enhanced mainly due to the migration of ionized drug molecules but also secondary effects e.g. electroosmotic convective flow and tissue alteration due to current can be responsible for the flux enhancement. Due to these secondary effects also the flux of neutral drug molecules is enhanced in the presence of electric field (L. Wearley & Y. W. Chien, Pharmaceutical Research Vol. 7, 1990, pp. 34-40).
When current is passing in the circuit electrochemical reactions take place at the electrodes, and possibly harmful reaction products can be generated or useful compounds consumed at the electrodes. Such a reaction is usually the splitting of water which results in the change of pH and in the need to buffer the solutions (see e.g. EP 369945). Iontophoretic burns, skin irritation and electric shocks have been reported (P. Tyle, Pharmaceutical Research, Vol. 3, No. 6, 1986, pp. 318-326 and A. K. Banga & Y. W. Chien, Journal of Controlled Release, Vol. 7, 1988, pp. 1-24).
SUMMARY OF THE INVENTION
The present invention provides an iontophoretic device in which the power to generate the necessary electropotential to deliver the drug is provided by a difference in concentration of a salt across an anion selective membrane and a cation selective membrane. There is no need for a conventional battery or any electrodes. The present invention therefore provides a method of administering a drug, which is ionized or ionizable in situ, to a human or animal body which method comprises forming a circuit by placing in electrolytic contact:
(i) the body and
(ii) one or more electrolyte solutions of which at least one is
REFERENCES:
patent: 542459 (1895-07-01), Beckwith
patent: 868123 (1907-10-01), Randall
patent: 4171409 (1979-10-01), Loeb
patent: 4722726 (1988-02-01), Sanderson et al.
patent: 4731049 (1988-03-01), Parsi
Banga and Chien, "Iontophoretic Delivery of Drugs: Fundamentals, Developments and Biomedical Applications," J. Controlled Release 7:1-24 (1988).
Bannon et al., "Iontophoretically Induced Transdermal Delivery of Salbutamol," Drug Devel. and Indust. Pharm. 14(15-17):2151-2166 (1988).
Chien et al., "Direct Current Iontophoretic Transdermal Delivery of Peptide and Protein Drugs," J. Pharm. Sci. 78(5):376-383 (1989).
Singh and Roberts, "Transdermal Delivery of Drugs by Iontophoresis: A Review," Drug Design and Delivery 4:1-12 (1989).
Tyle, P., "Iontophoretic Devices for Drug Delivery," Pharm. Res. 3(6):318-326 (1986).
Wearley and Chien, "Enhancement of the in Vitro Skin Permeability of Azidothymidine (AZT) via Iontophoresis and Chemical Enhancer," Pharm. Res. 7(1):34-40 (1990).
Weinstein and Leitz, "Electric Power from Differences in Salinity: The Dialytic Battery," Science 191:557-559 (1976).
Kontturi Kyosti E. A.
Murtomaki Lasse S.
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