Curcumin-loaded gold nanoparticles anchored carboxylated multiwalled carbon nanotubes: Formulation development and in vitro assessment as a drug delivery system for ovarian cancer treatment

We developed a novel class of curcumin (CUR)-loaded gold nanoparticles (AuNP)-anchored carboxylated multiwalled carbon nanotubes (c-MWCNTs) for ovarian cancer (OC) treatment. The AuNPs were synthesized using the Turkevich method. The c-MWCNTs were functionalized with AuNPs to enhance biocompatibility, loading capacity, and cellular uptake. Then, CUR was effectively loaded into AuNP-CNT nanoconjugates, which were subsequently coupled to folic acid (FA) as a ligand. Various techniques, such as Raman spectroscopy, Fourier-transform infrared (FTIR) spectroscopy, Energy-dispersive analysis (EDX) with X-ray diffraction (XRD), Dynamic light scattering (DLS), High-resolution transmission electron microscopy (HRTEM), and Field-emission scanning electron microscopy (FESEM), were used to characterize AuNPs, c-MWCNTs, AuNP-CNT composites, and AuNP-CNT-CUR-FA. The average zeta size and polydispersity index (PDI) of the AuNP-CNT-CUR-FA were found to be 439 nm and 0.557, respectively. The loading efficiency of the conjugates was estimated to be about 94%. Cytotoxicity was evaluated using the sulforhodamine B (SRB) assay with the OC cell line SK-OV-3. The pH-triggered drug release from AuNP-CNT-CUR-FA formulation was observed at both physiological and acidic pH over 96 h. The formulation followed the Korsmeyer-Peppas model for drug release kinetics at both pH levels, with R² values of 0.9789 and 0.9884, respectively. The GI 50 value represents the concentration required to inhibit growth by 50%. AuNP-CNT-CUR-FA conjugate demonstrated a remarkable decrease in cell proliferation, i.e., −30.2%, at 80 µg/mL. These data collectively highlight the promise of nanomaterials as an OC treatment strategy, demonstrating their low toxicity, improved drug targeting, and sustained release.