title: Optimizing immobilization of avidin on surface-modified magnetic nanoparticles: characterization and application of protein-immobilized nanoparticles.
abstract: A simple optimization method of immobilization of avidin on magnetic nanoparticles (MNPs)' surface was proposed in this study. The avidin-immobilized MNPs were then developed and used to immobilize a model enzyme [Horseradish peroxidase (HRP)]. The loading capacity (LC) and activity of avidin-immobilized MNPs were optimized through selecting the most appropriate nanoparticle's size and shape, glutaraldehyde concentration, cross-linking reaction time, ultrasonic processing time, and initial concentration of avidin. The LC under optimized conditions was 63.37 ± 1.29 mg avidin/g MNPs, and the immobilized protein was still able to maintain its high biological activity of 10.86 ± 0.13 U/mg (biotin-binding activity of nature avidin was 14.1 U/mg) and better thermal stability compared to free avidin. A highly reusable, stable, and easily recovered immobilized HRP was obtained using MNPs as carriers. The immobilized HRP was reused repeatedly more than 9 times and retained more than 65 % of its original activity.
authors.affiliation: National Engineering Laboratory for Rice and Byproduct Process, Faculty of Food Science and Engineering, Center South University of Forestry and Technology, Changsha, Hunan, 410004, People's Republic of China.
authors.forename: Tao
authors.initials: T
authors.lastname: Yang
authors.affiliation: National Engineering Laboratory for Rice and Byproduct Process, Faculty of Food Science and Engineering, Center South University of Forestry and Technology, Changsha, Hunan, 410004, People's Republic of China. sshuguo@163.com.|National Research and Development Center for Egg Processing, College of Food Science and Technology, Huazhong Agricultural University, 1 Shizishan Street, Wuhan, Hubei, 430070, People's Republic of China. sshuguo@163.com.
authors.forename: Shuguo
authors.initials: S
authors.lastname: Sun
authors.affiliation: National Research and Development Center for Egg Processing, College of Food Science and Technology, Huazhong Agricultural University, 1 Shizishan Street, Wuhan, Hubei, 430070, People's Republic of China. mameihuhn@163.com.
authors.forename: Meihu
authors.initials: M
authors.lastname: Ma
authors.affiliation: National Engineering Laboratory for Rice and Byproduct Process, Faculty of Food Science and Engineering, Center South University of Forestry and Technology, Changsha, Hunan, 410004, People's Republic of China.
authors.forename: Qinlu
authors.initials: Q
authors.lastname: Lin
authors.affiliation: National Engineering Laboratory for Rice and Byproduct Process, Faculty of Food Science and Engineering, Center South University of Forestry and Technology, Changsha, Hunan, 410004, People's Republic of China.
authors.forename: Lin
authors.initials: L
authors.lastname: Zhang
authors.affiliation: National Engineering Laboratory for Rice and Byproduct Process, Faculty of Food Science and Engineering, Center South University of Forestry and Technology, Changsha, Hunan, 410004, People's Republic of China.
authors.forename: Yan
authors.initials: Y
authors.lastname: Li
authors.affiliation: National Engineering Laboratory for Rice and Byproduct Process, Faculty of Food Science and Engineering, Center South University of Forestry and Technology, Changsha, Hunan, 410004, People's Republic of China.
authors.forename: Feijun
authors.initials: F
authors.lastname: Luo
mesh_terms: D000327:Adsorption; D001360:Avidin / Q000737:chemistry*; D001710:Biotin / Q000737:chemistry*; D020099:Coated Materials, Biocompatible / Q000138:chemical synthesis*; D004800:Enzymes, Immobilized / Q000737:chemistry; D006735:Horseradish Peroxidase / Q000737:chemistry*; D007118:Immunoassay / Q000379:methods*; D058185:Magnetite Nanoparticles / Q000737:chemistry* / Q000648:ultrastructure; D010316:Particle Size; D013499:Surface Properties
chemical_list: D020099:Coated Materials, Biocompatible; D004800:Enzymes, Immobilized; D058185:Magnetite Nanoparticles; D001360:Avidin; D001710:Biotin; D006735:Horseradish Peroxidase
keywords: Avidin; Biological activity; Horseradish peroxidase; Immobilization strategy; Magnetic nanoparticles