title: Biomagnetic of Apatite-Coated Cobalt Ferrite: A Core-Shell Particle for Protein Adsorption and pH-Controlled Release.
abstract: Magnetic nanoparticle composite with a cobalt ferrite (CoFe2O4, (CF)) core and an apatite (Ap) coating was synthesized using a biomineralization process in which a modified simulated body fluid (1.5SBF) solution is the source of the calcium phosphate for the apatite formation. The core-shell structure formed after the citric acid-stabilized cobalt ferrite (CFCA) particles were incubated in the 1.5 SBF solution for 1 week. The mean particle size of CFCA-Ap is about 750 nm. A saturation magnetization of 15.56 emug(-1) and a coercivity of 1808.5 Oe were observed for the CFCA-Ap obtained. Bovine serum albumin (BSA) was used as the model protein to study the adsorption and release of the proteins by the CFCA-Ap particles. The protein adsorption by the CFCA-Ap particles followed a more typical Freundlich than Langmuir adsorption isotherm. The BSA release as a function of time became less rapid as the CFCA-Ap particles were immersed in higher pH solution, thus indicating that the BSA release is dependent on the local pH.
authors: ThEP Center, Commission of Higher Education, 328 Si Ayuthaya Rd., Bangkok, 10400, Thailand.|Department of Physics, Faculty of Science, Mahidol University, Bangkok, 10400, Thailand.
authors: I-Ming
authors: IM
authors: Tang
authors: Consortium for Calcium and Bone Research, Faculty of Science, Mahidol University, Bangkok, 10400, Thailand.|Department of Physiology, Faculty of Science, Mahidol University, Bangkok, 10400, Thailand.
authors: Nateetip
authors: N
authors: Krishnamra
authors: Consortium for Calcium and Bone Research, Faculty of Science, Mahidol University, Bangkok, 10400, Thailand.|Department of Physiology, Faculty of Science, Mahidol University, Bangkok, 10400, Thailand.
authors: Narattaphol
authors: N
authors: Charoenphandhu
authors: ThEP Center, Commission of Higher Education, 328 Si Ayuthaya Rd., Bangkok, 10400, Thailand.|Mahidol University International College, Salaya Campus, Mahidol University, Salaya, 73720, Thailand.
authors: Rassmidara
authors: R
authors: Hoonsawat
authors: ThEP Center, Commission of Higher Education, 328 Si Ayuthaya Rd., Bangkok, 10400, Thailand. wponun@yahoo.com.
authors: Weeraphat
authors: W
authors: Pon-On
keywords: Apatite; Bovine serum albumin (BSA); Cobalt ferrite; Protein release