Photothermally Enhanced Chemotherapy Delivered by Graphene Oxide-Based Multiresponsive Nanogels

To develop multifunctional anticancer nanomedicines, photothermal nanogels with multistimulative properties are fabricated by hybridizing graphene oxide (GO) with poly(N-isopropylacrylamide, PNIPAM) matrix. This technique allows for easy monomer-intercalation between GO sheets, followed by in situ polymerization to promote GO exfoliation as nanoplatelets inside emulsified PNIPAM nanodrops, followed by fixation using a disulfide-containing cross-linker. The resulting nanogels own significantly improved colloidal stability and biocompatibility as compared to native GO. They can effectively encapsulate an anticancer drug and accelerate its release under conditions mimicking acidic/reducible solid tumor and intracellular microenvironments. Drug delivery can be further enhanced via remote photothermal treatment. The local photothermal effect and drug release smartness make the nanogels as an ideal nanoplatform for synergistic anticancer therapy upon their arrival at tumor tissue or inside cancer cells.