US 12,403,197 B2
Polymer system for ophthalmic drug delivery
Heather Sheardown, Hamilton (CA); Mitchell Ross, Hamilton (CA); and Talena Rambarran, Hamilton (CA)
Assigned to McMaster University, Hamilton (CA)
Filed by McMaster University, Hamilton (CA)
Filed on Dec. 9, 2021, as Appl. No. 17/546,645.
Claims priority of provisional application 63/123,173, filed on Dec. 9, 2020.
Prior Publication US 2022/0175932 A1, Jun. 9, 2022
Int. Cl. A61K 47/36 (2006.01); A61K 9/06 (2006.01); A61K 47/32 (2006.01); C08G 81/02 (2006.01); G02B 1/04 (2006.01)
CPC A61K 47/36 (2013.01) [A61K 9/06 (2013.01); A61K 47/32 (2013.01); C08G 81/02 (2013.01); G02B 1/043 (2013.01)] 19 Claims
 
1. A thermo-gel comprising:
a) a polymer comprising monomers N, A and X, wherein N is N-isopropylacrylamide (NIPAAm), A is acrylic acid (AA) and X is a hydrophobic monomer; and
b) about 1 wt % to about 5 wt % chitosan, wherein the chitosan has a weight average molecular weight of about 10 kDa to about 300 kDa,
wherein the chitosan is covalently or ionically bonded to the acrylic acid in the polymer, and wherein the acrylic acid is incorporated throughout the polymer, and
wherein the hydrophobic monomer (X) is selected from methyl acrylate, methyl methacrylate, ethyl acrylate, ethyl methacrylate, butyl acrylate, butyl methacrylate, isobutyl acrylate, isobutyl methacrylate, 2-ethylhexyl acrylate, tert-butyl acrylate, tert-butyl methacrylate, cyclohexyl methacrylate, phenyl methacrylate, 3-[tris(trimethylsiloxy)silyl]propyl methacrylate, pyridyl disulfide ethyl methacrylate 2-(pyridin-2-yldisulfaneyl)ethyl acrylate, N-(2-(pyridin-2-yldisulfaneyl)ethyl)methacrylamide, 3-(pyridin-2-yldisulfaneyl)propyl methacrylate, 2-(pyridin-2-yldisulfaneyl)ethyl methacrylate, 2-(2-pyridin-2-yldisulfanyl)ethyl-2-(methacrylamido)acetate and N-(3-(3-(pyridin-2-yldisulfanyl)propanamido)propyl)methacrylamide.