Preparation and investigation on properties of lysozyme chemically bonded to single-walled carbon nanotubes

The purpose of this research is the preparation of a lysozyme-single-walled carbon nanotube (SWCNT) conjugate and investigation of the effect of conjugation on the structure and function of lysozyme. At first, SWCNTs were functionalised by oxygen and lysozyme was coupled to the SWCNTs by carbodiimide method. The high chemical stability of conjugation was purposed for the SWCNTs conjugated enzyme as approved by Fourier transform infrared (FT-IR) spectroscopy, transmission electron microscopy (TEM) images, agarose gel electrophoresis and X-ray diffraction (XRD) patterns. The degree of conjugation was determined by thermogravimetric analysis (TGA) process. The results showed no significant differences between the XRD patterns of the native lysozyme and conjugated lysozyme–SWCNTs and these indicated excellent capacity of the SWCNTs to conjugated enzyme. The gel electrophoresis studies and TEM image confirmed the covalent attachment of the enzyme to the functionalised SWCNTs. These results revealed that the enzyme retain a high fraction of their native structure and activity upon attachment to SWCNTs. Therefore, this conjugated protein represents novel preparations that make it an attractive choice as a natural antimicrobial agent.

lysozyme; single-walled carbon nanotubes; enzyme conjugation