Methods for forming, modifying, and drug loading of a copolymer are provided, along with the resulting products. The method can include polymerizing 2-(pyridin-2-yldisulfanyl)ethyl acrylate with poly(ethylene glycol)methacrylate via free radical polymerization to form the copolymer. The molar ratio of 2-(pyridin-2-yldisulfanyl)ethyl acrylate to poly(ethylene glycol)methacrylate is about 100:1 to about 1:100. After polymerizing, the copolymer can be reacted with a thiol monomer that contains a carbon-bonded sulfhydryl to modify end groups on a first portion of the 2-(pyridin-2-yldisulfanyl)ethyl acrylate repeating units. Thereafter, the copolymer can be crosslinked, and a drug can then be loaded into the crosslinked copolymer.
