A microneedle for transdermal drug delivery, the microneedle comprising an input channel extending through the microneedle along a longitudinal axis of the microneedle, the input channel defining a sidewall, a first end, and a second end, the input channel configured to receive fluid input into the microneedle. The microneedle comprises one or more outlet channels extending between an interior surface of the sidewall, and an exterior surface of the sidewall, such that each of the one or more outlet channels define a fluid path between the input channel and the exterior surface of the sidewall. The one or more outlet channels are angled relative to the longitudinal axis of the microneedle at an angle which is greater than 0 and less than 90.

Provided herein are devices and methods for topically and controllably delivering cargo or collecting samples into or from biological tissues, particularly the skin. These devices permit delivery of cargo and collection of samples from cell layers deep within a tissue. These devices include microstructure arrays comprising nanochannels. Also disclosed is a device comprising a one or more microstructure arrays encased in a frame.

Methods and devices of collecting ISF from skin. The methods may include inserting an array of microneedles into a patient's skin to form apertures in the patient's skin, facilitating ISF mobilization within the skin, and collecting ISF that flows from the apertures. The devices may include an array of microneedles extending from a backing structure. The devices also may include a collection matrix for collecting ISF and/or means for facilitating ISF mobilization.

A dual chambered syringe includes: an inner barrel defining a first inner chamber, the inner barrel having an apertured stopper at its distal end, the inner barrel being open at its proximal end; a shaft adapted to fit within the inner barrel, the shaft having a distal end which is engageable with the aperture of the stopper; a device for controlling engaging and disengaging of the distal end of the shaft with the aperture of the stopper; an outer barrel concentric with the inner barrel defining a second inner chamber, the outer barrel having a distal end for receiving and dispensing fluids and a proximal end into which the distal end of the inner barrel is insertable into the second inner chamber; the apertured stopper engages the second inner chamber of the outer barrel and selectively prevents or permits the passage of fluids between the outer barrel second chamber and the inner barrel first chamber; the inner barrel having an engageable surface on its outside surface; and, the outer barrel having operatively associated therewith an engaging device for selective engagement and disengagement with the engageable surface on the inner barrel.

A silicon etched sharp bearing body may comprise a substrate. The sharp bearing body may further comprise a microneedle extending proud of a first side of the substrate. The microneedle may have a sloped face and sidewalls defining a tip region and a trailing region. The sidewalls at the tip region may be curved and devoid of straight spans. The sidewalls at the trailing region may be curved and devoid of straight spans. The sharp bearing body may further comprise a lumen extending through the sharp bearing body from a second side of the substrate opposite the first side and to the sloped face of the microneedle. The sharp bearing body may further comprise a trench recessed around the sidewalls of the microneedle. The wall of the trench most distal the sidewalls of the microneedle may be curved and devoid of straight spans.

A silicon etched sharp bearing body may comprise a substrate. The sharp bearing body may further comprise a microneedle extending proud of a first side of the substrate. The microneedle may have a sloped face and sidewalls defining a tip region and a trailing region. The sidewalls at the tip region may be curved and devoid of straight spans. The sidewalls at the trailing region may be curved and devoid of straight spans. The sharp bearing body may further comprise a lumen extending through the sharp bearing body from a second side of the substrate opposite the first side and to the sloped face of the microneedle. The sharp bearing body may further comprise a trench recessed around the sidewalls of the microneedle. The wall of the trench most distal the sidewalls of the microneedle may be curved and devoid of straight spans