US 6,256,533 B1 · Apparatus and method for using an intracutaneous microneedle array

Abstract

A microneedle array, constructed of silicon and silicon dioxide compounds or of a molded plastic material, is provided to penetrate the stratum corneum and epidermis layers of skin, but not into the dermis. The microneedles can be used to either dispense a liquid drug, or to sample a body fluid. The delivery of drugs and sampling of fluids can be performed by way of passive diffusion (time release), instantaneous injection, or iontophoresis. A complete closed-loop system can be manufactured including active elements, such as micro-machined pumps, as well as passive elements such as sensors. A “smart patch” can thereby be fabricated that samples body fluids, performs chemistry to decide on the appropriate drug dosage, and then administers the corresponding amount of drug. An electric field may be used to increase transdermal flow rate. Such a system can be made disposable, and can be used with medical devices to dispense drugs by iontophoretic/microneedle enhancement, to sample body fluids (while providing an iontophoretically/microneedle-enhanced body-fluid sensor), and as a closed-loop drug delivery system with fluid sampling feedback using a combination of the other two devices. As a drug dispensing system, the microneedle array includes electrodes that apply an electric potential to the skin between the electrode locations. One of the electrode assemblies is filled with an ionized drug, and the charged drug molecules move into the body due to the applied electric potential. As a body-fluid sampling system, the microneedle array also includes electrodes to assist in moving fluid from the body into a receiving chamber, and which further includes a bioelectrochemical sensor to measure the concentration of a particular substance.

Claims30

Dependent claims

A first structure comprising:

a first base element and first plurality of microneedles formed thereon, wherein said first base element has a first side and a second side;
wherein said first plurality of microneedles comprises a plurality of hollow elements which project from the second side of said first base element along longitudinal axes that are at an angle with respect to said first base element;
wherein at least one of said longitudinal axes of said first plurality of microneedles is in alignment with one of a plurality of first openings in the second side of said first base element;
wherein said hollow elements of said first plurality of microneedles allow liquid to flow therethrough between a plurality of second openings at a distal end of said hollow elements and said first openings at the second side of said first base element;
and a first container structure comprising:
(a) a first reservoir capable of holding a liquid, (b) a first electrode proximal to said first reservoir;
a second structure comprising:
a second base element and second plurality of microneedles formed thereon, wherein said second base element has a third side and a fourth side;
wherein said second plurality of microneedles comprises a plurality of hollow elements which project from the fourth side of said second base element along a longitudinal axis that is at an angle with respect to said second base element;
wherein at least one of said longitudinal axes of said second plurality of microneedles is in alignment with one of a plurality of third openings in the fourth side of said second base element;
wherein said hollow elements of said second plurality of microneedles allow liquid to flow therethrough between a plurality of fourth openings at a distal end of said hollow elements and said third openings at the fourth side of said second base element;
and a second container structure comprising:
(a) a second reservoir capable of holding a liquid,
(b) a second electrode proximal to said second reservoir;
and
an electrical power source that is in communication with said first and second electrodes.

13 more elements

A first structure comprising:

a first base element and first plurality of microneedles formed thereon, wherein said first base element has a first side and a second side;
wherein said first plurality of microneedles comprises a plurality of projections which extend from the second side of said first base element along a longitudinal axis that is at an angle with respect to said first base element;
wherein at least one of said longitudinal axes of said first plurality of microneedles is located proximal to a plurality of first openings in the second side of said first base element;
wherein said first plurality of microneedles allows liquid to flow along their outer surfaces through said first openings at the second side of said first base element;
and a first container structure comprising:
(a) a first reservoir capable of holding a liquid,
(b) a first electrode proximal to said first reservoir;
a second structure comprising:
a second base element and second plurality of microneedles formed thereon, wherein said second base element has a third side and a fourth side;
wherein said second plurality of microneedles comprises a plurality of projections which extend from the fourth side of said second base element along a longitudinal axis that is at an angle with respect to said second base element;
wherein at least one of said longitudinal axes of said second plurality of microneedles is located proximal to a plurality of second openings in the fourth side of said second base element;
wherein said second plurality of microneedles allows liquid to flow along their outer surfaces through said second openings at the fourth side of said second base element;
and a second container structure comprising:
(a) a second reservoir capable of holding a liquid,
(b) a second electrode proximal to said second reservoir;
and
an electrical power source that is in communication with said first and second electrodes.

14 more elements

A method for dispensing liquid into a body through its skin, comprising:

(a) providing a first structure comprising:
a first base element and first plurality of microneedles formed thereon, wherein said first base element has a first side and a second side;
wherein said first plurality of microneedles comprises a plurality of hollow elements which project from the second side of said first base element along a longitudinal axis that is at an angle with respect to said first base element;
wherein at least one of said longitudinal axes of said first plurality of microneedles is in alignment with one of a plurality of first openings in the second side of said first base element;
wherein said hollow elements of said first plurality of microneedles allow liquid to flow therethrough between a plurality of second openings at a distal end of said hollow elements and said first openings at the second side of said first base element;
and a first iontophoresis apparatus comprising:
(i) a first reservoir for holding a liquid that is to be dispensed, (ii) a first electrode proximal to said first reservoir;
(b) providing a second structure comprising:
a second base element and second plurality of microneedles formed thereon, wherein said second base element has a third side and a fourth side;
wherein said second plurality of microneedles comprises a plurality of hollow elements which project from the fourth side of said second base element along a longitudinal axis that is at an angle with respect to said second base element;
wherein at least one of said longitudinal axes of said second plurality of microneedles is in alignment with one of a plurality of third openings in the fourth side of said second base element;
wherein said hollow elements of said second plurality of microneedles allow liquid to flow therethrough between a plurality of fourth openings at a distal end of said hollow elements and said third openings at the fourth side of said second base element;
and a second iontophoresis apparatus comprising:
(i) a second reservoir for holding a liquid, (ii) a second electrode proximal to said second reservoir;
(c) providing an electrical power source that is in communication with said first and second electrodes;
wherein said first and second electrodes facilitate dispensing said liquid through said plurality of microneedles into skin by iontophoresis;
(d) placing said first and second structures on skin in different locations, such that at least one of said first plurality of microneedles penetrates through a stratum corneum and into an epidermis of said skin, and that at least one of said second plurality of microneedles penetrates through said stratum corneum and into said epidermis;
and
(e) dispensing liquid from said first reservoir into said epidermis by applying an electrical potential between said first and second electrodes.

16 more elements

A method for sampling body-fluid of an organism through its skin, comprising:

(a) providing a first structure comprising:
a first base element and first plurality of microneedles formed thereon, wherein said first base element has a first side and a second side;
wherein said first plurality of microneedles comprises a plurality of hollow elements which project from the second side of said first base element along a longitudinal axis that is at an angle with respect to said first base element;
wherein at least one of said longitudinal axes of said first plurality of microneedles is in alignment with one of a plurality of first openings in the second side of said first base element;
wherein said hollow elements of said first plurality of microneedles allow liquid to flow therethrough between a plurality of second openings at a distal end of said hollow elements and said first openings at the second side of said first base element;
and a sensing apparatus comprising:
(i) a first reservoir for holding a liquid that is to be sampled, (ii) a first electrode proximal to said reservoir at a first location, (iii) a second electrode proximal to said reservoir at a second location which detects an electrical signal in the manner of a bioelectrochemical sensor;
(b) providing a second structure comprising:
a second base element and second plurality of microneedles formed thereon, wherein said second base element has a third side and a fourth side;
wherein said second plurality of microneedles comprises a plurality of hollow elements which project from the fourth side of said second base element along a longitudinal axis that is at an angle with respect to said second base element;
wherein at least one of said longitudinal axes of said second plurality of microneedles is in alignment with one of a plurality of third openings in the fourth side of said second base element;
wherein said hollow elements of said second plurality of microneedles allow liquid to flow therethrough between a plurality of fourth openings at a distal end of said hollow elements and said third openings at the fourth side of said second base element;
and a reverse iontophoresis apparatus comprising:
(i) a second reservoir for holding a liquid, (ii) a third electrode proximal to said second reservoir;
(c) providing an electrical power source that is in communication with said first and third electrodes;
an electronic controller;
wherein said first and third electrodes facilitate body-fluid sampling of a body fluid from skin through said plurality of microneedles by reverse iontophoresis;
(d) placing said first and second structures on skin in different locations, such that at least one of said first plurality of microneedles penetrates through a stratum corneum and into an epidermis of said skin, and that at least one of said second plurality of microneedles penetrates through said stratum corneum and into said epidermis;
and
(e) withdrawing liquid from said epidermis into said first reservoir by applying an electrical potential between said first and third electrodes.

17 more elements

A method for dispensing liquid into a body through its skin, comprising:

(a) providing a first structure comprising:
a first base element and first plurality of microneedles formed thereon, wherein said first base element has a first side and second side;
wherein said first plurality of microneedles comprises a plurality of projections which extend from the second side of said first base element along a longitudinal axis that is at an angle with respect to said first base element;
wherein at least one of said longitudinal axes of said plurality of microneedles is located proximal to a plurality of first openings in the second side of said first base element;
wherein said first plurality of microneedles allows liquid to flow along their outer surfaces through said first openings at the second side of said first base element;
and a first iontophoresis apparatus comprising:
(i) a first reservoir for holding liquid to be dispensed, (ii) a first electrode proximal to said first reservoir;
(b) providing a second structure comprising:
a second base element and second plurality of microneedles formed thereon, wherein said second base element has a third side and a fourth side;
wherein said second plurality of microneedles comprises of plurality of projections which extend from the fourth side of said second base element along a longitudinal axis that is at an angle with respect to said second base element;
wherein at least one of said longitudinal axes of said second plurality of microneedles is located proximal to a plurality of second openings in the fourth side of said second base element;
wherein said second plurality of microneedles allows liquid to flow along their outer surfaces through said second openings at the fourth side of said second base element;
and a second iontophoresis apparatus comprising:
(i) a second reservoir for holding a liquid, (ii) a second electrode proximal to said second reservoir;
(c) providing an electrical power source that is in communication with said first and second electrodes;
wherein first and second electrodes facilitate dispensing said liquid along outer surfaces of said first plurality of microneedles through said second openings into skin by iontophoresis;
(d) placing said first and second structures on skin in different locations, such that at least one of said first plurality of microneedles penetrates through a stratum corneum and into an epidermis of said skin, and at least one of said second plurality of microneedles penetrates through said stratum corneum and into said epidermis;
and
(e) dispensing liquid from said first reservoir into said epidermis by applying an electrical potential between said first and second electrodes.

16 more elements

A method for sampling body fluid of an organism through its skin, comprising:

(a) providing a first structure comprising:
a first base element and first plurality of microneedles formed thereon, wherein said first base element has a first side and second side;
wherein said first plurality of microneedles comprises a plurality of projections which extend from the second side of said first base element along a longitudinal axis that is at an angle with respect to said first base element;
wherein at least one of said longitudinal axes of said plurality of microneedles is located proximal to a plurality of first openings in the second side of said first base element;
wherein said first plurality of microneedles allows liquid to flow along their outer surfaces through said first openings at the second side of said first base element;
and a sensing apparatus comprising:
(i) a first reservoir for holding a liquid that is to be sampled, (ii) a first electrode proximal to said reservoir at a first location (iii) a second electrode proximal to said reservoir at a second location which detects an electrical signal in the manner of a bioelectrochemical sensor;
(b) providing a second structure comprising:
a second base element and second plurality of microneedles formed thereon, wherein said second base element has a third side and a fourth side;
wherein said second plurality of microneedles comprises of plurality of projections which extend from the fourth side of said second base element along a longitudinal axis that is at an angle with respect to said second base element;
wherein at least one of said longitudinal axes of said second plurality of microneedles is located proximal to a plurality of second openings in the fourth side of said second base element;
wherein said second plurality of microneedles allows liquid to flow along their outer surfaces through said second openings at the fourth side of said second base element;
and a reverse iontophoresis apparatus comprising:
(i) a second reservoir for holding a liquid, (ii) a third electrode proximal to said second reservoir;
(c) providing an electrical power source that is in communication with said first and third electrodes;
an electronic controller;
wherein first and third electrodes facilitate body-fluid sampling of a body fluid along outer surfaces of said first plurality of microneedles through said second openings from skin by reverse iontophoresis;
(d) placing said first and second structures on skin in different locations, such that at least one of said first plurality of microneedles penetrates through a stratum corneum and into an epidermis of said skin, and at least one of said second plurality of microneedles penetrates through said stratum corneum and into said epidermis;
and
(e) withdrawing liquid from said epidermis into said first reservoir by applying an electrical potential between said first and third electrodes.

17 more elements

Dependencies are inferred from the claim text.

Apparatus and method for using an intracutaneous microneedle array

Life of this patent

Apparatus and method for using an intracutaneous microneedle array

Life of this patent

Abstract

Claims30