Thermosensitive polymer (N-isopropylacrylamide) coated nanomagnetic particles: Preparation and characterization
| Autor: | M.S. Uddin, Liang Hong, Nabila Shamim, Kus Hidajat |
|---|---|
| Rok vydání: | 2007 |
| Předmět: |
Thermogravimetric analysis
Materials science Surface Properties Acrylic Resins Analytical chemistry Nanoparticle Ferric Compounds Magnetics Colloid and Surface Chemistry X-ray photoelectron spectroscopy Particle Size Physical and Theoretical Chemistry Fourier transform infrared spectroscopy chemistry.chemical_classification Molecular Structure Temperature Surfaces and Interfaces General Medicine Polymer Polymerization chemistry Chemical engineering Nanoparticles Particle Adsorption Biotechnology Superparamagnetism |
| Zdroj: | Colloids and Surfaces B: Biointerfaces. 55:51-58 |
| ISSN: | 0927-7765 |
| DOI: | 10.1016/j.colsurfb.2006.11.007 |
| Popis: | Thermosensitive polymer coated nanomagnetic adsorbents were synthesized by seed polymerization using surface modified nanomagnetic particles as the seeds. The Fe3O4 nanomagnetic particles were prepared by chemical precipitation of Fe2+ and Fe3+ salts in the ratio of 1:2 under alkaline and inert condition. The surface of these particles was modified by surfactants to achieve stability against agglomeration. These stable particles were then polymerized using N-isopropylacrylamide (NIPAM) as the main monomer, methylene-bis-acrylamide as the crosslinker and potassium per sulfate as the initiator. The thermosensitive adsorbents were characterized by using transmission electron micrography (TEM) and vibrating sample magnetometer (VSM). TEM showed that the particle remained discrete with a mean diameter of 12 nm. Magnetic measurements revealed that the particles are superparamagnetic only with a decrease of magnetism after binding with the polymer due to the increase in surface spin disorientation. Pure Fe3O4 spinel structure of these nanoparticles was indicated by the X-ray diffraction (XRD) patterns. The polymerization of NIPAM with the surface modified nanomagnetic particles was confirmed by Fourier transform spectroscopy (FTIR), Thermogravimetric analysis (TGA) and X-ray photoelectron spectroscopy (XPS). In addition, the adsorption/desorption of BSA molecule on these thermosensitive nanoparticles was investigated as a function of temperature. More than 60% desorption efficiency was achieved under appropriate condition. |
| Databáze: | OpenAIRE |
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