RESUMEN
A facile AAO (anodic aluminum oxide) template-assisted vacuum die-casting technique was used to create Sn nanowires and convert them into SnO2 without degrading the wires nanostructure. As a function of time and temperature, the controlled oxidation on the Sn nanowires of two different spatial configurations (100 and 250 nm in diameter) revealed distinct oxidation mechanisms. The 250-SnO2 nanowires exhibits a peculiar crumb-like structure formation over the surface due to the higher level of Sn atom dislocation. Conversely, the sub-100 nm SnO2 nanowires shows a highly crystalline, homogenous, and defect-free surfaces. The optical properties of the sub-100 nm SnO2 nanowires were characterized using UV-Vis spectroscopy. The heat-treated tin oxides nanowires samples at temperatures of 300, 500, and 700 °C for 7 h exhibited optical energy bandgaps of 1.8, 2.6, and 3.3 eV, respectively. The observed variation in bandgap is attributed to the unique phase compositions achieved in each of the heat-treated samples. Moreover, the obtained results showed exceptional structural integrity and optical properties that are inherently interconnected with the diverse phases achieved under precise heat treatment conditions.
RESUMEN
Exosomes, small vesicles of endocytic origin, have attracted attention in bone regeneration field. The vesicles travel between cells and deliver functional cargoes like proteins and RNAs, thereby regulating targeted cells dif-ferentiation, commitment, function, and proliferation. Exosomes directly regulate MSCs into the osteoblastic lineage, stimulate bone regeneration by directly regulating osteoblast proliferation and activity, regulate osteoclast maturation and activity and stimulate bone growth and regeneration by increasing vessel formation. Meantime, exosomes resolves toxicity and immunogenicity problems caused by biomaterial treatment. Furthermore, compared with living cell trans-plantation, exosomes present a lower risk for severe complication(such as tumors, emboli formation).
