US 12,403,292 B2
Microneedles and methods of manufacture thereof
Devin McAllister, Marietta, GA (US); Mark R. Prausnitz, Atlanta, GA (US); Sebastien Henry, Smyrna, GA (US); and Xin Dong Guo, Atlanta, GA (US)
Assigned to Georgia Tech Research Corporation, Atlanta, GA (US)
Filed by Georgia Tech Research Corporation, Atlanta, GA (US)
Filed on Aug. 14, 2023, as Appl. No. 18/233,397.
Application 17/061,203 is a division of application No. 15/306,152, granted, now 10,828,478, issued on Nov. 10, 2020, previously published as PCT/US2015/027672, filed on Apr. 24, 2015.
Application 18/233,397 is a continuation of application No. 17/061,203, filed on Oct. 1, 2020, granted, now 11,724,079.
Claims priority of provisional application 61/983,593, filed on Apr. 24, 2014.
Prior Publication US 2023/0381478 A1, Nov. 30, 2023
This patent is subject to a terminal disclaimer.
Int. Cl. A61M 37/00 (2006.01)
CPC A61M 37/0015 (2013.01) [A61M 2037/0023 (2013.01); A61M 2037/0046 (2013.01); A61M 2037/0053 (2013.01)] 39 Claims
OG exemplary drawing
 
1. A method for making a microneedle array, the method comprising:
(a) providing a mold having an upper surface and an opening in the upper surface, wherein the opening leads to a first cavity proximal to the upper surface and to a plurality of second cavities below the first cavity, wherein the first cavity defines a primary funnel portion, and wherein the second cavities define an array of microneedles;
(b) loading into the second cavities a first material which comprises a substance of interest dissolved or suspended in a first liquid vehicle;
(c) drying the first material in the mold to remove at least a portion of the first liquid vehicle to form at least a tip portion of a microneedle in each of the second cavities, wherein the tip portion comprises the substance of interest;
(d) loading the first cavity and a proximal portion of the second cavities unoccupied following steps (b) and (c) with a second material which comprises a matrix material dissolved or suspended in a second liquid vehicle;
(e) drying the second material in the mold to remove at least a portion of the second liquid vehicle to form (i) a primary funnel portion, and (ii) proximal portions of the microneedles, wherein the primary funnel portion comprises the matrix material,
wherein the formed tip portions and proximal portions of the microneedles together with the formed primary funnel portion are the microneedle array, and
wherein at least step (b) comprises spinning the mold in a centrifuge to create a gravitational force to drive the first material into the second cavities.