Materials and methods for delivering compositions to selected tissues
This invention relates to devices, systems and methods for delivering preprogrammed quantities of an active ingredient to a biological system over time without the need for external power or electronics.
1. A method of preparing a composition for controlled drug delivery comprising:
providing a porous silicon film;
heating the porous silicon film in an oxidizing environment at a temperature above 600° C.,
preparing particles from the oxidized porous silicon film; and
treating the oxidized porous silicon particles with a drug or biologically active material.
2. The method of claim 1 , wherein the particles have a size of between about 0.1 μm and about 100 μm.
3. The method of claim 1 , wherein the porous silicon film comprises pores with a free volume of from 50% to 80%.
4. The method of claim 1 , wherein the drug or biologically active material is a protein.
5. The method of claim 4 , wherein the drug or biologically active material is bevacizumab, ranibizumab, or pegaptanib.
6. The method of claim 1 , wherein the drug of biologically active material is selected from the group consisting of angiostatic steroids, metalloproteinase inhibitors, VEGF binding drugs, PEDF, an 8-mer peptide fragment of urokinase (uPA), and dexamethasone.
7. The method of claim 1 , wherein the drug or biologically active material targets a disease or disorder of the eye.
8. The method of claim 7 , wherein the disease or disorder of the eye is selected from the group consisting of: age-related macular degeneration (AMD), choroidal neovascularization (CNV), uveitis, diabetic retinopathy, retinovasclar disease, retinal detachment (PVR), and glaucoma.
9. The method of claim 1 , wherein the porous silicon film comprises a layered nanostructure.
10. The method of claim 1 , comprising the step of heating the porous silicon film in an oxidizing environment at a temperature above 700° C.
11. The method of claim 1 , comprising the step of heating the porous silicon film in an oxidizing environment at a temperature above 800° C.
12. The method of claim 1 , wherein particles are prepared from the oxidized porous silicon film after the porous silicon film is heated in an oxidizing environment at a temperature above 600° C.
13. The method of claim 1 , wherein the porous silicon film comprises pores selectively dimensioned to obtain a desired reflective wavelength.
14. The method of claim 1 , further comprising the step of capping the porous silicon film with a polymeric material.
15. The method of claim 1 , wherein the porous silicon film comprises pores configured to enhance binding efficacy of the drug or biologically active material.