Biotin-Conjugated Polypyrrole-Coated Graphene Oxide Nanoplatform for Tumor-Targeted IR820 Delivery and Chemophotothermal Therapeutic Benefit in Cancer

Abstract

A carbon-based, multifunctional nanoformulation that combines chemotherapy and photothermal therapy has been developed for targeted cancer treatment. IR820, a NIR light-activated photothermal and diagnostic agent, was loaded into graphene oxide coated with polypyrrole [GO(P)], which generates up to 57 °C under an 808 nm NIR laser, inducing tumor apoptosis and necrosis. Surface modification was done using poloxamer (F127) and tumor-targeting ligand, biotin (B), and the biotin density was optimized by finding the highest biotin percentage leading to receptor saturation. 1H NMR and GPC confirmed the conjugation of F127 and Biotin. The resulting IR820@GO(P)F and IR820@GO(P)FB nanoparticles were characterized using FTIR, DLS, SEM, AFM, encapsulation efficiency, drug loading, release, and stability studies in different storage conditions. In vitro studies on SKBr3 spheroids demonstrated effective uptake, ROS generation, mitochondrial disruption, and apoptosis, as confirmed by the upregulation of apoptotic (Caspase 7, Caspase 9, and Bax) and downregulation of proliferative (Bcl-2) markers via Western blot analysis. In vivo biodistribution and ex vivo fluorescence studies performed in a tumor-bearing Balb/c mouse model confirmed better drug accumulation and lesser clearance of IR820@GO(P)FB NPs to evaluate tumor specificity. In conclusion, the developed carbon-based nanoplatform showed significant tumor specificity and inhibition, making it a significant approach for a potential multifunctional treatment strategy for cancer.