Abstract: Improved microneedle arrays are provided having a sufficiently large separation distance between each of the individual microneedles to ensure penetration of the skin while having a sufficiently small separation distance to provide high transdermal transport rates. A very useful range of separation distances between microneedles is in the range of 100-300 microns, and more preferably in the range of 100-200 microns. The outer diameter and microneedle length is also very important, and in combination with the separation distance will be crucial as to whether or not the microneedles will actually penetrate the stratum corneum of skin. For circular microneedles, a useful outer diameter range is from 20-100 microns, and more preferably in the range of 20-50 microns.

Abstract: Improved microneedle arrays are provided having a sufficiently large separation distance between each of the individual microneedles to ensure penetration of the skin while having a sufficiently small separation distance to provide high transdermal transport rates. A very useful range of separation distances between microneedles is in the range of 100–300 microns, and more preferably in the range of 100–200 microns. The outer diameter and microneedle length is also very important, and in combination with the separation distance will be crucial as to whether or not the microneedles will actually penetrate the stratum corneum of skin. For circular microneedles, a useful outer diameter range is from 20–100 microns, and more preferably in the range of 20–50 microns.

Abstract: A hollow microneedle with a substantially sharp edge is provided that includes at least one longitudinal blade at the top surface or tip of the microneedle to aid in penetration of the stratum corneum of skin. In a preferred embodiment, there are two such longitudinal blades that are constructed on opposite surfaces at approximately a 180° angle along the cylindrical side wall of the microneedle. Each edged blade has a cross-section that, when viewed from above the microneedle top, has an isosceles triangle profile. The blade's edge can run the entire length of the microneedle from its very top surface to its bottom surface where it is mounted onto the substrate, or the edge can be discontinued partway down the length of the microneedle. A star-shaped solid microneedle also is provided having at least one blade with a relatively sharp edge to assist in penetrating the stratum corneum of skin.

Abstract: An array of microneedles is provided to apply semi-permanent or permanent markings to skin, or to apply semi-permanent subcutaneous makeup or other cosmetic compounds to skin. The microneedles can apply identifications or other tattoo-like graphics, and will not enter into the dermal layer of the skin so that the application procedure is painless. The microneedle array is also useful for delivering specific compounds or actives into the skin, such as cosmetic compounds or nutrients, or various skin structure modifiers that can be delivered subcutaneously without having to visit a cosmetic surgery clinic.

Abstract: Test strips and methods are provided for use in the determination of the concentration of at least one target analyte in a physiological sample. The subject test strips include a plurality of skin-piercing elements affixed thereto. In the subject methods, the plurality of skin-piercing elements affixed to the test strip is inserted into the skin, physiological sample is transferred to the test strip and the concentration of an analyte is determined. The subject test strips and methods find use in a variety of different applications, particularly in the determination of glucose concentrations.

Abstract: An array of hollow microneedles is constructed of molded plastic, in which a micro-machining technique is used to fabricate the molds used in a plastic microforming process. The molds are detachable and can be re-used. The preferred process for making the plastic arrays of microneedles is a microinjection technique. In the microinjection method, a molten plastic substance is injected between two micro-machined molds that contain microhole and micropillar arrays. Once the desired shape of the microneedle array has been formed, the mold and the plastic material are cooled down. Next, the molds are separated and the plastic microneedle array is detached from the mold structures.

Abstract: A microneedle array is manufactured using a mold preparation procedure that begins by placing an optical mask over a layer of PMMA material, exposing the PMMA material to x-rays, then developing using a photoresist process. The remaining PMMA material is then electroplated with metal. Once the metal has reached an appropriate thickness, it is detached to become a metal mold that is used in a microembossing procedure, in which the metal mold is pressed against a heated layer of plastic material. Once the mold is pressed down to its proper distance, the plastic material is cooled until solidified, and the mold is then detached, thereby leaving behind an array of microneedles.

Abstract: A first embodiment microneedle array is constructed of silicon and silicon dioxide compounds using MEMS technology and standard microfabrication techniques to create hollow cylindrical individual microneedles. The resulting array of microneedles can penetrate with a small pressure through the stratum corneum of skin to either deliver drugs or to facilitate interstitial fluid sampling through the hollow microneedles into the epidermis. The delivery of drugs and sampling of fluids can be performed by way of passive diffusion (time release), instantaneous injection, or iontophoresis. In a second embodiment, an array of hollow (or solid) microneedles is constructed of plastic or some other type of molded or cast material. An electric field may be used to increase transdermal flow rate, and the microneedles can be effectively combined with the application of an electric field between an anode and cathode attached to the skin which causes a low-level electric current.

Abstract: One embodiment of a microneedle array is constructed of silicon and silicon dioxide compounds using MEMS technology and standard microfabrication techniques to create hollow cylindrical individual microneedles. The resulting array of microneedles is designed to penetrate the stratum corneum and epidermis layers of skin, but not into the dermis. In a second embodiment, an array of hollow (or solid) microneedles are constructed of molded plastic, in which a micro-machining technique is used to fabricate the molds used in a plastic microforming process. Such molds contain a micropillar array and/or microhole array. The manufacturing procedures for creating plastic arrays of microneedles include: “self-molding,” micromolding, microembossing, and microinjection techniques. In the “self-molding” method, a plastic (e.g.

Abstract: A microneedle array is constructed of silicon and silicon dioxide compounds using MEMS (i.e., Micro-Electro-Mechanical-Systems) technology and standard microfabrication techniques. The microneedle array may be fabricated from a silicon die which can be etched in a microfabrication process to create hollow cylindrical individual microneedles. The resulting array of microneedles can penetrate with a small pressure through the stratum corneum of skin (including skin of animals, reptiles, or other creatures—typically skin of a living organism) to either deliver drugs or to facilitate interstitial fluid sampling through the hollow microneedles.

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.