The Physics Society of Iran Iranian Journal of Physics Research 1682-6957 25 2 2025 09 23 Investigation of the effect of polyethyleneimine and dextran coatings on the structural and magnetic properties of magnetite nanoparticles Investigation of the effect of polyethyleneimine and dextran coatings on the structural and magnetic properties of magnetite nanoparticles 337 344 3698 10.47176/ijpr.25.2.62130 FA Hossein Nikmanesh Department of Physics, Persian Gulf University, Bushehr 75169, Iran 0000-0001-5515-5702 Fatemeh Doryani Department of Biological Science & Technology, Persian Gulf University, Bushehr 75169, Iran Abbas Bechachari Department of Physics, Persian Gulf University, Bushehr 75169, Iran Amirhossein Ahmadi Department of Biological Science & Technology, Persian Gulf University, Bushehr 75169, Iran Journal Article 2025 06 26 In this study, the effects of polyethyleneimine and dextran polymers as polymeric coatings on the structural, morphology, and magnetic properties of magnetite iron oxide nanoparticles were investigated using the co-precipitation method. The samples were prepared using standard methods, and their structural and magnetic properties were examined through analyses such as XRD, FTIR, FESEM, SAED, HRTEM, and VSM. The findings of this research indicate that both coatings maintain the spinel structure of Fe₃O₄; however, the polymeric coatings induce differences in surface spin canting and magnetic anisotropy. The results show that the nanoparticles coated with polyethyleneimine are significantly larger than the pure magnetite and dextran-coated magnetite nanoparticles, and they exhibit reduced agglomeration and better stability. On the other hand, the dextran coating, due to its thinner organic layers, leads to greater particle aggregation and higher saturation magnetization. In fact, dextran-coated nanoparticles create steric hindrances that result in different aggregation behaviors. In this study, the effects of polyethyleneimine and dextran polymers as polymeric coatings on the structural, morphology, and magnetic properties of magnetite iron oxide nanoparticles were investigated using the co-precipitation method. The samples were prepared using standard methods, and their structural and magnetic properties were examined through analyses such as XRD, FTIR, FESEM, SAED, HRTEM, and VSM. The findings of this research indicate that both coatings maintain the spinel structure of Fe₃O₄; however, the polymeric coatings induce differences in surface spin canting and magnetic anisotropy. The results show that the nanoparticles coated with polyethyleneimine are significantly larger than the pure magnetite and dextran-coated magnetite nanoparticles, and they exhibit reduced agglomeration and better stability. On the other hand, the dextran coating, due to its thinner organic layers, leads to greater particle aggregation and higher saturation magnetization. In fact, dextran-coated nanoparticles create steric hindrances that result in different aggregation behaviors. https://ijpr.iut.ac.ir/article_3698_943aa0fcda4ee2901a7de9321663b114.pdf