Chitosan–SiO 2–multiwall carbon nanotubes nanocomposite: A novel matrix for the immobilization of creatine amidinohydrolase

Abstract

A matrix made up of chitosan–SiO 2–multiwall carbon nanotubes (CHIT–SiO 2–MWCNTs) nanocomposite was fabricated to investigate the immobilization of creatine amidinohydrolase (CAH). CAH enzyme was covalently immobilized with the CHIT–SiO 2–MWCNTs matrix using glutaraldehyde as a linker. The resulting CAH/CHIT–SiO 2–MWCNTs biomatrix was characterized with Fourier transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM) and cyclic voltammetry (CV) taking CHIT–SiO 2–MWNTs as a reference. The influence of various parameters on CAH enzyme activity within the matrix was investigated including pH, temperature, and time. The Michaelis–Menten constant and apparent activities for the CAH enzyme were calculated to be 0.58 mM and 83.16 mg/cm 2, respectively; indicating CHIT–SiO 2–MWCNTs nanocomposite matrix has a high affinity to immobilize CAH enzyme.