Titanium-protein nanocomposites as new biomaterials produced by high-pressure torsion.

The development of new biomaterials with outstanding mechanical properties and high biocompatibility has been a significant challenge in the last decades. Nanocrystalline metals have provided new opportunities in producing high-strength biomaterials, but the biocompatibility of these nanometals needs to be improved. In this study, we introduce metal-protein nanocomposites as high-strength biomaterials with superior biocompatibility.

Glycine amino acid transformation under impacts by small solar system bodies, simulated via high-pressure torsion method.

Impacts by small solar system bodies (meteoroids, asteroids, comets and transitional objects) are characterized by a combination of energy dynamics and chemical modification on both terrestrial and small solar system bodies. In this context, the discovery of glycine amino acid in meteorites and comets has led to a hypothesis that impacts by astronomical bodies could contribute to delivery and polymerization of amino acids in the early Earth to generate proteins as essential molecules for life. Besides the possibility of abiotic polymerization of glycine, its decomposition by impacts could generate reactive groups to form other essential organic biomolecules.

Ultrahigh hardness and biocompatibility of high-entropy alloy TiAlFeCoNi processed by high-pressure torsion.

Despite significant studies on mechanical properties of high-entropy alloys (HEAs), there have been limited attempts to examine the biocompatibility of these alloys. In this study, a lattice-softened high-entropy alloy TiAlFeCoNi with ultrahigh hardness (examined by Vickers method), low elastic modulus (examined by nanoindentation) and superior activity for cell proliferation/viability/cytotoxicity (examined by MTT assay) was developed by employing imperial data and thermodynamic calculations. The designated alloy after casting was processed further by high-pressure torsion (HPT) to improve its hardness via the introduction of nanograins, dislocations and order-disorder transformation.