In recent years, magnetic nanoparticles (MNPs) have been applied to numerous biological systems. The nanoparticles are particularly useful in separating biological molecules due to its low price, scalable ability and very little interference. Here, MNPs, which can efficiently separate biocatalysts from reaction media by external magnet, was used to immobilize an alkaline protease (Alcalase R ). | Communications in Physics, Vol. 24, No. 3S1 (2014), pp. 121-126 DOI: R IMMOBILIZING ALCALASE ENZYME ONTO MAGNETIC NANOPARTICLES CAO XUAN HUU Department of Electronics & Telecommunication Engineering, Da Nang University of Technology NGUYEN BAO LINH, NGUYEN THI HOANG YEN, DANG DUC LONG Department of Chemistry Engineering, Da Nang University of Technology E-mail: huucao78@ Received 04 April 2014 Accepted for publication 24 May 2014 Abstract. In recent years, magnetic nanoparticles (MNPs) have been applied to numerous biological systems. The nanoparticles are particularly useful in separating biological molecules due to its low price, scalable ability and very little interference. Here, MNPs, which can efficiently separate biocatalysts from reaction media by external magnet, R was used to immobilize an alkaline protease (Alcalase ). Covalent attachment of the enzyme to MNPs began with the functionalization of the MNPs’ surface with amines (APTES). Then, glutaraldehyde was introduced to link the MNP surface amines with enzyme surface amine residues, typically lysine. Successful covalent bonds were checked by FT-IR. Our results showed the attached enzyme did not affect superparamagnetic property of MNPs, therefore the MNPs-attached enzyme was easily recovered after the reaction. The immobilized enzyme maintained its activities after 10 times of recycle uses. Keywords: magnetic nanoparticles, alkaline protease, enzyme immobilization, glutaraldehyde. I. INTRODUCTION In recent years, magnetic nanoparticles (MNPs) have been applied to numerous biological systems due to their high saturation magnetization, their biocompatibility, their stability under hard condition, and the simplicity of their preparation process [1,2]. MNPs have been used in drug delivery system, protein separation, enzyme and protein immobilization [3] and diagnostics [4]. In those applications, the surface of MNPs needs to be functionalized and attach to .
