Preparation Of Magnetic Nanocomposite And Its Application In Diagnosis And Therapy

Cancer,a major threat to human health,is difficult to achieve early diagnosis and effective treatment so that patients' survival rate has been at a low level.Scientists are committed to researching new types of imaging contrast agents and high-efficiency therapeutic agents to change this situation.While the appearance and rapid development of nanomaterials,especially magnetic nanomaterials,fit well with this appeal.The traditional treatment methods of cancer,chemotherapy and radiotherapy,can inhibit tumor growth to a certain extent.However,these methods suffer from the lack of selectivity,causing serious side effects and damage to healthy tissue after treatment.Due to these defects,targeted drug delivery systems,radiation sensitizers and new treatment means such as photothermal therapy are becoming research hotspots in the field of biomedicine.And the combination of multiple treatment methods has been a new trend in cancer treatment.In the field of diagnosis,imaging technologies like magnetic resonance imaging and computed tomography are indispensable.How to increase the imaging efficiency as much as possible in the existing equipment and maximize the contrast has become an urgent problem to be solved.Nanocomposites that combine a variety of imaging capabilities can minimize the dosage of contrast agents under the premise of maintaining or improving the contrast effect.Which undoubtedly has a broad application prospect in the future medical imaging.This paper is based on magnetic nanocomposites and explores their effectiveness as therapeutics and contrast agents.The main work is as follows:?1?In this study,uniform Fe₃O₄ NPs were synthesized,which were then coated with mesoporous silica and followed by modified with peptide.And this nanomaterial was used as enzyme-response targeted drug delivery system.The enzyme responsiveness and biocompatibility of this system was tested by in vitro drug release and cell experiments.The animal experiments were used to study the anticancer efficiency and systemic toxicity of this drug carrier.?2?In this paper,Fe@Bi₂S₃ nanocomposites with uniform size were synthesized and used as MRI/CT dual mode contrast agent and PTT/RT combined therapeutic agent after PEG modification.Both cell and animal experiments were used to explore the efficacy of combination therapy.