NaHoF 4 @PDA Nanoparticles In MR/PA Imaging And Photothermal Therapy

Rare earth ions exhibit unique optical and magnetic properties owing to their unique 4f electron configurations.Therefore,rare earth nanoparticles have been widely used as magnetic resonance imaging?MRI?and optical imaging contrast agents.This thesis focuses on the synthesis and MRI of NaHo F₄ nanoparticles.Polydopamine?PDA?was modified on the surface of NaHo F₄ nanoparticles to perform photoacoustic imaging and photothermal therapy.Part 1.Oleic acid stabilized NaDyF₄ and NaHoF₄ nanoparticles were synthesized by solvo-thermal method,respectively.Polyacrylic acid?PAA2000?was further modified by the ligand exchange method to improve the water solubility.The nanoparticles exhibit uniform size and good dispersibility.Considering of the magnetic properties of PAA-Na DyF₄ and PAA-NaHo F₄ nanoparticles,they can be used as MRI contrast agents.Part 2.In order to realize the integration of the diagnosis and treatment of tumor,polydopamine?PDA?was modified on the surface of NaHoF₄ nanoparticles by in-situ self-polymerization,which can increase its absorption in the near-infrared region,and endow them the functions of photoacoustic imaging and photothermal therapy.PEG was further modified on the surface of PDA conjugated NaHoF₄ nanoparticles to increase their biocompatibility.Notably,the resultant nanoparticles exhibit the small biological toxicity,and can be used for MRI,photoacoustic imaging,and photothermal therapy.Part 3.In order to improve the targeting property of nanoparticles,DGEA was modified on the PDA conjugated NaHo F₄ nanoparticles to target prostate cancer.After the modification of DGEA?Asp-Gly-Glu-Ala?,nanoparticles have good dispersibility and biocompatibility.The nanoparticles can be further used in vivo targeted magnetic resonance imaging,photoacoustic imaging,and photothermal therapy.