Comparison of the deposition of Laccase bio-coatings on two carbon nanomaterials

Deposition of biologically active coatings by plasma is currently of interest as application of plasma methods allows simpler, single step deposition with reduction in biocoating times from hours to minutes. Biocoatings can be successfully deposited using the SPP (Soft Plasma Polymerization) method based on helium carrier gas, pin-to-plane, atmospheric pressure, room temperature corona discharges with low energy density. Deposition of Laccases is significant because of their wide application in biotechnology, sensing and environmental protection. In such deposition carbon nanomaterials are frequently used in the form of solid supports. Therefore, the aim of this work was the comparison of Laccase biocoatings deposited by SPP plasma jet onto glass slides modified by graphene oxide and multi-walled carbon nanotube coatings. Experiments showed that deposition of Laccase onto these nanomaterials very likely involves different mechanisms. The presence of hydroxyl and carboxyl groups in the structure of graphene oxide allows creation of covalent, amide bonds with the Laccase molecule. The chemical structure of multi-walled carbon nanotubes, however, can include only bonding with carbon atoms suggesting that the deposition of Laccase onto MWCNT occurs dominantly by a physical adsorption process.