Cur-loaded magnetic ZnFe2O4@mZnO-Ox-p-g-C3N4 composites as dual pH- and ultrasound responsive nano-carriers for controlled and targeted cancer chemotherapy

Abstract

Curcumin (Cur)-loaded zinc ferrite-mesoporous (m) zinc oxide core–shell -oxygen functional groups (carboxyl, carbonyl and hydroxyl) rich mesoporous (p) graphitic (g) carbon nitride (ZnFe2O4@mZnO-Ox-p-g-C3N4) carriers were designed as a potential magnetic drug delivery carrier with pH and ultrasound sensitivity for targeted drug delivery. Application of focused ultrasound can be an effective stimulant for highlighting tumor tissue or activatng delivery of echogenic drugs, which is expected to lower the systemic side effects of chemotherapy. The mixed application of physical/external (ultrasound) and chemical/internal (pH) triggers can allow for targeted release of Cur at chosen sections of tumor tissue. ZnFe2O4@mZnO and ZnFe2O4@mZnO-p-g-C3N4 nano-carriers were characterized using field emission scanning electron microscopy (FESEM), energy-dispersive X-ray analysis (EDX), X-ray diffraction (XRD), Fourier rransform infra-red (FTIR) spectroscopy, dynamic light scattering (DLS), zeta potential analysis, transmission electron microscopy (TEM), BET (Brunauer–Emmett–Teller), vibrating sample magnetometery (VSM), thermogravimetric analysis (TGA) and in vitro cytotoxicity assays. The ZnFe2O4@mZnOand ZnFe2O4@mZnO-Ox-p-g-C3N4 magnetic nano-carriers showed high loading efficiency of 51.39 and 67.37%, respectively, were stable in water for 24 h. The carriers Nano-carriersshowed pH- and ultrasound-sesnsitive release of Cur. The release at pH = 5.5 for (ZnFe2O4@mZnO 70.28%) (ZnFe2O4@mZnO-Ox-p-g-C3N4 56.05%) was more than that at pH = 7.4 for (ZnFe2O4@mZnO 66.26%) (ZnFe2O4@mZnO-Ox-p-g-C3N4 45.40%) after 72 h.