Synthesis Of Novel Magnetic Nanoparticles And Its Application In Drug Delivery System

With the development of nanotechnology,nanocarrier has been applied in all aspects of biomedicine,including bacterial/cell screening,biological imaging and drug delivery.The magnetic nanocarrier can enhance permeability and retention effect to enrich the drug loaded in the lesion site,which reduce the side effects and improve the efficacy.Magnetic Fe₃O₄ nanoparticles are widely used as drug carriers because of their stable chemical properties,stable magnetic properties,large specific surface area,and good biocompatibility.And they can be modified by chemical methods to improve their performance.In this paper,Fe3O4 nanocarriers are synthesized and their performances for doxorubin delivery are examined.?1?Magnetic Fe₃O₄@PEG Nanoparticles Synthesis and Application for Doxorubicin DeliveryFe₃O₄ nanoparticles were prepared by co-precipitation method,and citric acid was added into the solution to improve the dispersion of magnetic nanoparticles.Then di-carboxylic polyethylene glycol?COOH-PEG-COOH?was connected to the surface of Fe₃O₄ nanoparticles through the ester bond with the aim of improving the hydrophilicity of Fe₃O₄ nanoparticles,prolonging the circulation time of Fe3O4 nanoparticles in vivo,and accumulating more drug molecules on the carrier surface.Thus the modified Fe3O4 magnetic nanoparticle carrier was obtained,and the structural of the synthesized magnetic nanoparticle carrier was be characterized.Doxorubicin?DOX?was electrostatically attached to nanoparticles to study the nanocarriers loading and release behavior.The experimental results show that the drug loading rate of Fe₃O₄@PEG magnetic nanoparticles is 85%and the sustained-release effect is good.In addition,in vivo the magnetic nanocarrier shows good cell viability and the magnetic nanocarrier loaded with doxorubicin tumor activity and doxorubicin antitumor activity quite.?2?Magnetic Fe3O4@SiO2-PEG Nanoparticles Synthesis and Application for Doxorubicin DeliveryMagnetic nanocarrier with core-shell structure was synthesized and employed in drug delivery system to reduce the adverse effection.More specifically,we prepared Fe3O4@SiO2 through a bi-phase approach,then the core-shell Fe₃O₄@SiO₂ nanoparticles were functionalized with di-carboxylic polyethylene glycol?COOH-PEG-COOH?after Fe3O4@SiO2 nanoparticles have been modified with 3-Aminopropyltriethoxysilane,Fe3O4@SiO2-PEG nanoparticles was synthesised via an amide bond.The morphology,structure,stability,and performance characteristics of the synthesized nanoparticles were characterized.Furthermore,Doxorubicin?DOX?,as the model medicine,was loaded in the Fe₃O₄@SiO₂-PEG nanoparticles to test the load and release behaviors of Fe₃O₄@SiO₂-PEG/DOX.The the drug loading rate of Fe₃O₄@SiO₂-PEG nanocarrier is about 92%and its cumulative release rate was higher at pH 5.0 compared to pH 7.4.Meanwhile,the toxicity of synthetic drug delivery system was studied by MTT assay.The results show that the synthesized Fe3O4@SiO2-PEG nanoparticles provide a prospect application for cancer treatment as drug delivery in t an extra magnetic field environment.?3?Magnetic GO-Fe₃O₄@SiO₂ Nanoparticles Synthesis and Application for Doxorubicin DeliveryGO and Fe₃O₄@SiO₂ were connected through amide bond to obtain GO-Fe₃O₄@SiO₂.More specifically,Fe₃O₄@SiO₂ was aminated with the 3-aminopropyltriethoxysilane?APTES?,then it was connected with the carboxyl group of GO via an amide bond.doxorubicin?DOX?connected to the nanoparticles via?-?interaction.Finally,MTT assay was performed to study the cytotoxicity of GO-Fe₃O₄@SiO₂/DOX.The function of GO is to improve the biocompatibility and drug loading of Fe3O4@SiO2 nanpcarriers because of its good water solubility and specific surface area.GO-Fe3O4@SiO2/DOX can be easy constructed because GO is hexagonal structure.The model drug DOX was used to study the drug-loading and drug-releasing behaviors of GO-Fe3O4@SiO2.The results showed that GO-Fe3O4@SiO2 exhibited superparamagnetism with a loading efficiency of 82%,and the cell viability gradually decreased with increasing GO-Fe₃O₄@SiO₂/DOX concentration.