Mendonça BHS, de Moraes EE, Kirch A, Batista RJC, de Oliveira AB, Barbosa MC, Chacham H.
Flow through Deformed Carbon Nanotubes Predicted by Rigid and Flexible Water Models. The Journal of Physical Chemistry B [Internet]. 2023.
Publisher's Version Pinto AA, de Moraes EE, Chacham H, Batista RJC.
Modulation of spin and charge currents through functionalized 2D diamond devices. Nanotechnology [Internet]. 2023;35:075704.
Publisher's VersionAbstractIn this study, we explore the potential of functionalized two-dimensional (2D) diamond for spin-dependent electronic devices using first-principles calculations. Specifically, we investigate functionalizations with either hydroxyl (−OH) or fluorine (−F) groups. In the case of an isolated layer, we observe that the quantity and distribution of (−OH) or (−F) on the 2D diamond surface significantly influence the sp 2/sp 3 ratio of the carbon atoms in the layer. As the coverage is reduced, both the band gap and magnetic moment decrease. When the 2D diamond is placed between gold contacts and functionalized with (−OH), it results in a device with lower resistance compared to the (−F) functionalization. We predict that the maximum current achieved in the device increases with decreasing (−OH) surface coverage, while the opposite behavior occurs for (−F). Additionally, the surface coverage alone can alter the direction of current rectification in (−F) functionalized 2D diamonds. For all studied systems, a single spin component contributes to the total current for certain values of applied bias, indicating a spin filter behavior.
Mendonça BHS, de Moraes EE, Batista, Ronaldo J. C. AU - de Oliveira AB, de Oliveira AB, Barbosa MC, Chacham H.
Water Diffusion in Carbon Nanotubes for Rigid and Flexible Models. The Journal of Physical Chemistry C [Internet]. 2023.
Publisher's Version Marinho JPN, Neme NP, de Matos MJS, Campos Batista RJ, de Macedo WAA, Gastelois PL, Gomes DA, Rodrigues MA, Cipreste MF, de Sousa EMB.
Nanostructured system based on hydroxyapatite and curcumin: A promising candidate for osteosarcoma therapy. Ceramics International [Internet]. 2023.
Publisher's VersionAbstractOsteosarcoma is the most common type of bone cancer. Despite therapeutic progress, survival rates for metastatic cases or that do not respond well to chemotherapy remain in the 30% range. In this sense, the use of nanotechnology to develop targeted and more effective therapies is a promising tool in the fight against cancer. Nanostructured hydroxyapatite, due to its biocompatibility and the wide possibility of functionalization, is an interesting material to design nanoplatforms for targeted drug delivery. These platforms have the potential to enable the use of natural substances in the fight against cancer, such as curcumin. Curcumin is a polyphenol with promising properties in treating various types of cancer, including osteosarcoma. In this work, hydroxyapatite (n-HA) nanorods synthesized by the hydrothermal method were investigated as a carrier for curcumin. For this, first-principle calculations based on the Density Functional Theory (DFT) were performed, in which the modification of curcumin (CM) with the coupling agent (3-aminopropyl) triethoxysilane (APTES) was theoretically evaluated. Curcumin was incorporated in n-HA and the drug loading stability was evaluated by leaching test. Samples were characterized by a multi-techniques approach, including Fourier transform infrared spectroscopy (FTIR), UV–visible spectroscopy (UV–Vis), X-ray diffraction (XRD), X-ray fluorescence spectrometry (FRX), thermogravimetric analysis (TGA), differential scanning calorimetry (DSC), zeta potential analysis (ζ), X-ray photoelectron spectroscopy (XPS) and transmission electron microscopy (TEM). The results show that n-HAs with a 90 nm average size were obtained and successful incorporation of curcumin in the nanostructure was achieved. Cell viability and the number of osteosarcoma cells were decreased by CMAP-HA treatment. Furthermore, the stability test suggests that hydroxyapatite nanoparticles present great potential for the transportation of curcumin in the bloodstream, crediting this system for biological performance evaluations aiming at the treatment of osteosarcomas. Keywords: nanostructures, curcumin, hydroxyapatite, osteosarcoma.