Systems and methods for the transport of fluids through a biological barrier and production techniques for such systems
A device for the transport of fluids through a biological barrier includes a number of microneedles projecting from the front face of a substrate. A conduit is associated with each of the microneedles to provide a fluid flow path for transport of fluid through a hole in the biological barrier formed by the corresponding microneedle. Each of the microneedles is configured to provide a penetrating tip, and each conduit terminates at an opening which is proximal with respect to the microneedle tip. Also described are microneedle-based devices with integrated MEMS pumping configurations for withdrawal and/or delivery of fluids, and remote healthcare systems based on such devices.
1. A device for the transport of fluids through a biological barrier, the device comprising:
(a) a substrate having a front surface;
(b) an array of microneedles projecting from said front surface, each of said microneedles having a maximum width dimension of no more than about 400 μm and a maximum height dimension of no more than about 2 mm, each of said microneedles including:
(i) a penetrating tip,
(ii) at least one inclined surface extending from said penetrating tip towards said front surface of the substrate, and
(iii) an enclosed fluid flow channel formed through the microneedle and intersecting with said inclined surface,
wherein, in a cross-section through said microneedle adjacent to said front surface of said substrate, said fluid flow channel defines a first area having a first centroid and an outline of said microneedle defines a second area having a second centroid, said first and second centroids being non-coincident.
2. A device for the transport of fluids through a biological barrier, the device comprising:
(a) a substrate having a front surface;
(b) an array of microneedles projecting from said front surface, each of said microneedles having a maximum width dimension of no more than about 400 μm and a maximum height dimension of no more than about 2 mm, each of said microneedles including:
(i) a penetrating tip,
(ii) at least one inclined surface extending from said penetrating tip towards said front surface of the substrate, an entirety of said at least one inclined surface being inclined, and
(iii) a fluid flow channel formed through the microneedle and intersecting with said inclined surface,
such that, in a cross-section through said microneedle adjacent to said front surface of said substrate, said fluid flow channel is circumscribed by a closed wall, a first region of said closed wall having a thickness greater than that of a second region of said closed wall.
3. The device of claim 2 , wherein said first region and said second region lie substantially on opposite sides of said fluid flow channel.
4. The device of claim 2 , wherein the thickness of said closed wall in said first region is at least twice the thickness of said closed wall in said second region.
5. The device of claim 2 , wherein the thickness of said closed wall in said first region is at least equal to a maximum dimension of said fluid flow channel as viewed in said cross-section.