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In this manuscript, we report a study on the removal of contaminant methylphenidate from aqueous solution, including ab initio simulations and experimental adsorption, applying graphene oxide and reduced graphene oxide as adsorbents.

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The objective of this study was to evaluate the influence of vitamin C (VC) on the stability of stored liposomes under different climatic conditions. Liposomal formulations containing 1 mg/mL of VC (LIP-VC) and blank formulations (LIP-B) were prepared by the reverse-phase evaporation method. After preparation, they were characterized according to their refractive index, average vesicle diameter, polydispersity index (PDI), zeta potential, pH, content, encapsulation efficiency (EE%), morphology, stability and antioxidant activity. For stability, LIP-VC and LIP-B were stored in different climatic conditions (4 °C, 25 °C and 40 °C) for 30 days. The LIP-VC presented 1.3365 refractive index, 161 nm of mean diameter, 0.231 PDI, -7.3 mV zeta potential, 3.2 pH, 19.4% EE%, spherical morphology, 1 mg/mL of VC content, and antioxidant activity of 12 and 11.4 μmol of TE/mL for the radical DPPH and ABTS + , respectively. During stability, the LIP-B stored in 40 °C showed an instability in the parameters: PDI, vesicle size and zeta potential after 15 days, while the LIP-VC remained stable in its size and PDI for 30 days. After that, it is shown that VC can be used as an antioxidant and stabilizer in liposomes to increase the stability and shelf-life of vesicles.

To present a possible new alternative for wound treatment, this work evaluated the biological safety and therapeutic efficacy of graphene oxide (GO) and reduced graphene oxide (rGO) nanoparticles (NPs). First, the nanostructures were studied in silico and showed to be able to inhibit the production of some pro-inflammatory cytokines and stimulate the production of the anti-inflammatory cytokine IL-10, especially rGO. The results of the morphological and structural characterization of GO NPs synthesized from the Hummers method and reduced by ascorbic acid, were consistent with the literature, confirming their achievement. In the broth microdilution assay, GO and rGO showed antimicrobial activity against the clinical isolate of Streptococcus agalactiae (S. agalactiae) at a minimum inhibitory concentration (MIC) of 625 µg/mL for GO and 312.5 µg/mL for rGO. In addition, the nanostructure of rGO was able to inhibit, in subinhibitory concentration, the formation of S. agalactiae biofilm by up to 77% when compared to the positive control. Both NPs, in all tested concentrations, did not cause hemolysis, and alterations in coagulation in vitro assays. However, in the safety tests, it was evidenced that only the MIC of 312, µg/mL for rGO was biologically safe and presented anti-inflammatory and healing behavior in vitro. In general, the present work confirmed rGO's potential in the treatment of chronic wounds, since in silico showed anti-inflammatory behavior and in vitro showed therapeutic efficacy at low concentrations, prevented biofilm formation, and showed no significant toxic effects.

In this work we evaluated the structural and electronic properties of C-doped and COOH-functionalized β 12 borophene through ab initio simulations using the density functional theory (DFT). β 12 borophene is a stable 2D nanomaterial and composed only by B atoms, with promising applications specially for the electronic industry. The substitutional C-doped β 12 borophene is chemically favorable with a strong hybridization of carbon-boron energy levels. The COOH-functionalization on β 12 borophene presents high energy adsorption (around 3.2 eV). The studied functionalizations show metallic electronic properties in the resulting systems, as well as observed for pristine β 12 borophene.