Multifunctional Magnetic Nanocapsules For Targeted Photodynamic Therapy And MR Imaging For Gastric Cancer

Research backgroundGastric cancer is a malignant tumor in the digestive system.The number of gastric cancer patients has been gradually increasing,while the mortality rate induced by gastric cancer remain at a high level in word.In the recent five years,gastric cancer have emerged as the third cause of mortality rate of cacer in china,and the incidence rate is second.Although standard gastric cancer treatment strategies,including surgery,chemotherapy,and radiotherapy can significantly improve five-year survival rate,many disadvantages related to these procedures.Therefore,the development technology of early diagnosis and accurate treatment are of great importance.Magnetic nanoparticles and photothermal therapy(PPT)have been applied in the field of gastric cancer to improve the efficacy of therapeutic and diagnostic.For nanoparticles,they have unique physico-chemical properties,such as easy surface modification,long-term blood circulation,biocompatibility and large specific surface areas.PDT as an emerging clinical treatment means that could be widely used in the biomedical field.PDT shows several advantages,including simplicity of operation,high enrichment efficiency of tumor region,and minimal damage to normal tissues.Under near-infrared laser irradiation,tumor tissue could be irreversible damaged by photosensitizer molecules produce singlet oxygen.These two methods will provide novel thought for clinical diagnosis and treatment.The research methods and purposeIn this study,multifunctional co-loaded magnetic nanocapsules(MNCPs)were synthesized using the microemulsion method,and further coupled folic acid(FA)to the surface of the capsules to obtained PMA-Co@Mn/Ce6-FA MNPs.First,we observed the morphology,size,and distribution of the capsule by electron microscope.The encapsulating rate and loading rate of Ce6 were calculated via the standard curve of Ce6.Secondly,MGC-803 of gastric cancer cells was incubated with MNCPs to obtained the effect uptake and toxicity of cells.Finally,we observed the distribution,the effects of photodynamic therapy and nuclear magnetic resonance imaging(MRI)of MNCPs by injected MNCPs into mice.The results demonstrated that we have successfully synthesized multifunctional co-loaded magnetic nanocapsules that could be applied to bimodal imaging,targeted photodynamic therapy,and enhanced(MRI).The research results will provide a promising method and research platform for clinical integration of diagnosis and treatment in the near future.The research results1.The obtained MNCPs exhibit a spherical structure with a smooth surface,high dispersion,and uniform particle size in this study.The encapsulating rate and loading rate of Ce6 were 96%and 3.2,respectively.Furthermore,MNCPs shows a good stability at room temperature.2.In cell experiments,MGC-803 cells of gastric cancer exhibit a good uptake effect for MNCPs,and MNCPs have excellent compatibility with gastric cancer MGC-803 cells.3.Animal experiments show that MNCPs can enhancing the effect of targeted photodynamic therapy,nuclear magnetic resonance imaging and real-time fluorescent labeling for gastric cancer.The conclusion of the researchWe have successfully fabricated a multifunctional co-loaded magnetic nanocapsules.This research shows that MNCPs have favorable biocompatibility,high drug loading efficiency,excellent T2 relaxation values,long-term stability and uniform sizes(dc:?150 nm).These advantages can be applied to enhancing real-time fluorescent labeling,magnetic imaging in vitro and photodynamic therapy for gastric cancer.