Surface reactivity of rapidly quenched nano-quasicrystalline ribbons with respect to biomolecules

In this paper, we report on preliminary investigations about surface reactivity of quasicrystalline-based alloys with respect to small biological molecules such as amino-acids. The main purpose is to study potential applications for these materials in biomedical fields since biomolecules are well known to be sensitive to solid surface wettability, surface energy and charge. In that sense, quasicrystals surfaces could be attractive considering their unusual symmetry, their low surface energy and their peculiar electronic properties. Our investigations were focussed on superficial reactivity of as-quenched Ti45Zr38Ni17 (numbers indicate at.%) ribbons, whose microstructure was analysed by transmission electron microscopy and X-ray diffraction. Surfaces were then carefully polished and immersed in a solution (C = 10−2 mol l−1, pH 6) of l-glutamic acid or l-lysine for duration varying from 30 min to 6 days. Molecular vibrational modes and adsorption kinetics were investigated using infrared spectroscopy. The first results reveal that l-glutamic acid seems to display faster adsorption kinetic on quasicrystalline ribbons compared to that on pure titanium (cpTi) or on β-metastable alloys (Ti–12 Mo–6 Zr–4.5 Sn), which is quite interesting since surface energy on quasicrystals is known to be low.