CPC A61K 9/5192 (2013.01) [A61K 9/5073 (2013.01); A61K 9/5115 (2013.01)] | 31 Claims |
1. A method of preparing a controlled or delayed release pharmaceutical composition comprising:
i. a plurality of coated particles of a size that is from 0.1 μm to 50 μm, said coated particles having a solid core comprising a biologically active substance, said solid core being enclosed by one or more coatings comprising zinc oxide; and
ii. a pharmaceutically acceptable carrier, the method comprising the sequential steps of:
(1) applying an initial coating comprising zinc oxide to said solid cores in an atomic layer deposition reactor;
(2) discharging the coated particles from the reactor and subjecting the coated particles to agitation to disaggregate particle aggregates formed during step (1);
(3) reintroducing the disaggregated, coated particles from step (2) into an atomic layer deposition reactor and applying a further coating comprising zinc oxide to the reintroduced particles;
(4) optionally repeating steps (2) and (3) one or more times to increase total thickness of the coatings comprising zinc oxide that enclose said solid core; and
(5) admixing said coated particles obtained from step (3) or step (4) with said pharmaceutically acceptable carrier to form said pharmaceutical composition.
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