Research On Synergistic Cancer Phototherapy By Functional LDH-based Nanocomposites

CoFe-LDH nanosheets containing Fe³⁺were prepared using Co?NO₃?₂·6H₂O and Fe?NO₃?₃·9H₂O as raw materials by standard co-precipitation method with hydrothermal treatment.A multifunctional nanocomposite LDH-Hep-IR783 was constructed by loading the photosensitizer IR783 and heparin onto the nanosheets via electrostatic interaction.The morphology and structure of nanocomposite were characterized by scanning electron microscope?SEM?,transmission electron microscope?TEM?,and diffraction of X-rays?XRD?.The elemental composition of the nanocomposites was analyzed by X-ray photoelectron spectroscopy?XPS?and energy dispersive X-ray spectroscopy?EDS?.The spectrophotometry?UV?experiments results of dynamic light scattering?DLS?and ultraviolet-visible shows that the prepared nanocomposite drugs present good medium stability in vitro and its average hydrodynamic diameter will not change significantly for 7 days.The nanocomposites could increase local temperature and singlet oxygen?¹O₂?production significantly and exhibit excellent photothermal?PTT?and photodynamic?PDT?effect in vitro by near-infrared laser(2 W/cm^-2,808 nm)irradiation.Considering the catalysis between Fe³⁺and H₂O₂,more oxygen was produced to overcome the hypoxia tumor microenvironment thereby enhancing the efficacy of PDT.The anticoagulation experiments in vitro demonstrated that nanocomposites were equipped with excellent anticoagulant activity.In addition,the inhibition behavior of nanocomposites on VEGF has a potential gain effect on vivo therapyThe endocytosis behavior and cytotoxicity of the nanocomposites were observed by a HeLa cell model.The nanocomposites did not have any cytotoxicity in dark conditions but exhibited significant lethality of cancer cells under laser irradiation and almost all HeLa cells were apoptotic at a drug dose of 50?g/mL.The tumor inhibition in vivo was evaluated by establishing the xenograft uterine cervical cancer cells?U14?tumor models and histological staining confirmed the low toxic side effects of nanocomposites.The growth of mice solid tumors was significantly inhibited after treatment,and the nanocomposites showed good biocompatibility with negligible damage to normal organs and tissues.Therefore,LDH-Hep-IR783 provide new perspectives in the design of multifunctional nanomedicine,which shows promising applications in controlled drug delivery and cancer threatment.