Antifouling potential of Subtilisin A immobilized onto maleic anhydride copolymer thin films

Abstract

The proteinaceous nature of the adhesives used by most fouling organisms to attach to surfaces suggests that coatings incorporating proteolytic enzymes may provide a technology for the control of biofouling. In the present article, the antifouling (AF) and fouling release potential of model coatings incorporating the surface-immobilized protease, Subtilisin A, have been investigated. The enzyme was covalently attached to maleic anhydride copolymer thin films; the characteristics of the bioactive coatings obtained were adjusted through variation of the type of copolymer and the concentration of the enzyme solution used for immobilization. The bioactive coatings were tested for their effect on the settlement and adhesion strength of two major fouling species: the green alga Ulva linza and the diatom Navicula perminuta. The results show that the immobilized enzyme effectively reduced the settlement and adhesion strength of zoospores of Ulva and the adhesion strength of Navicula cells. The AF efficacy of the bioactive coatings increased with increasing enzyme surface concentration and activity, and was found to be superior to the equivalent amount of enzyme in solution. The results provide a rigorous analysis of one approach to the use of immobilized proteases to reduce the adhesion of marine fouling organisms and are of interest to those investigating enzyme-containing coating technologies for practical biofouling control.

Keywords:

• immobilized enzymes
• maleic anhydride copolymers
• Subtilisin Carlsberg
• antifouling
• Ulva
• Navicula

Acknowledgements

The authors express their gratitude to Ms Christine Arhnold, Messrs Dimitar Stamov, and Andreas Janke (members of the Max Bergmann Center of Biomaterials Dresden) for support in the preparation of MA coatings and AFM imaging, respectively, and to Ms Kerstin Voelz (member of the University of Birmingham) for assistance with the execution of the biological assays. The Research Technology Center of the Leibniz Institute of Polymer Research Dresden is gratefully acknowledged for assistance with the design and construction of the enzyme immobilization chambers. This work was supported by a grant from the AMBIO project (NMP4-CT-2005-011827) funded by the sixth Framework Program of Research and Technological Development of the European Community.

Additional information

Notes on contributors

Carsten Werner

The first two authors contributed equally to this work.