Effect of Ferric Ions on the Mechanical Strength of Marine Mussel Adhesive Proteins

Abstract

Mussel adhesive protein (MAP) is expected to be used as a new bioadhesive. However, the mechanical properties of MAP have not been reported, despite the potential importance of MAP in medical applications. The study aims to estimate the mechanical strength of MAP, and describe the influence of ferric ions present in MAP on the mechanical strength. Fe3+ incorporated in MAP is regarded as having an important role in the mechanical properties. Mussels were classified into two groups in order to compare the effect of Fe3+ on both the tensile and peel properties of MAP. One group was exposed to artificial seawater with a high concentration of ferric ions, and the other group is exposed to natural seawater as a control. The results revealed that the deterioration of the adhesive strength over time was different between the two groups, although significant differences in the tensile properties were not observed. While the adhesive strength in the control group decreased with elapsed time, it was increased for the iron-enriched group over the first 17 days. This suggested that ferric ions may improve the magnitude of the adhesive strength for MAP.

Keywords

• mussel
• adhesive protein
• biomaterial
• adhesive strength
• mechanical properties
• ferric ion
• peel test