Patent ID: 8920625
Filing Date: 2014-12-30
Classification: A61K,C01B,C01P,C25F,Y10T

Abstract:
1. A method of making porous particles comprising: providing a substrate having a surface; forming a first nanoporous layer in the substrate by electrochemical etching using a constant current density; continuing the etching by increasing the current density to form in the substrate a release layer, below the first nanoporous layer, having a porosity larger than that of the first nanoporous layer by electrochemical etching; depositing a protective layer onto the substrate; patterning the protective layer; wherein the patterning of the protective layer determines the lateral shape of the porous particles; etching the unprotected substrate to form pillars under the protective layer; removing the remaining protective layer; and releasing the one or more particles from the substrate, wherein the releasing comprises breaking the second porous layer and wherein the released one or more particles contain at least a portion of the first porous layer.