Herein, we study the feasibility of using nanocellulose (NC)-based composites with silver and platinum nanoparticles as additive materials to fabricate the support layer of thin film composite (TFC) membranes for water purification applications. In brief, the NC surface was chemically modified and then was decorated with silver and platinum nanoparticles, respectively, by chemical reduction. These metalized nanocellulose composites (MNC) were characterized by several techniques including: FTIR, XPS, TGA, XRD, and XANES to probe their integrity. Thereafter, we fabricated the MNC-TFC membranes and the support layer was modified to improve the membrane properties. The membranes were thoroughly characterized, and the performance was evaluated in forward osmosis (FO) mode with various feed solutions: nanopure water, urea, and wastewater samples. The fabricated membranes exhibited finger-like pore morphologies and varying pore sizes. Interestingly, higher water fluxes and solute rejection was obtained with the MNC-TFC membranes with wastewater samples. The overall approach of this work provides an effort to fabricated membranes with high water flux and enhanced selectivity.

In this work, we explore the use of electrochemical methods (i.e., impedance) along with the arsenic-specific aptamer (ArsSApt) to fabricate and study the interfacial properties of an arsenic (As(III)) sensor. The ArsSApt layer was self-assembled on a gold substrate, and upon binding of As(III), a detectable change in the impedimetric signal was recorded because of conformational changes at the interfacial layer. These interfacial changes are linearly correlated with the concentration of arsenic present in the system. This target-induced signal was utilized for the selective detection of As(III) with a linear dynamic range of 0.05–10 ppm and minimum detectable concentrations of ca. 0.8 μM. The proposed system proved to be successful mainly because of the combination of a highly sensitive electrochemical platform and the recognized specificity of the ArsSApt toward its target molecule. Also, the interaction between the ArsSApt and the target molecule (i.e., arsenic) was explored in depth. The obtained results in this work are aimed at proving the development of a simple and environmentally benign sensor for the detection of As(III) as well as in elucidating the possible interactions between the ArsSApt and arsenic molecules.

Interfacial surface properties, both physical and chemical, are known to play a critical role in achieving longterm stability of cell−biomaterial interactions. Novel bone tissue engineering technologies, which provide a suitable interface between cells and biomaterials and mitigate aseptic osteolysis, are sought and can be developed via the incorporation of nanostructured materials. In this sense, engineered nanobased constructs provide an effective interface and suitable topography for direct interaction with cells, promoting faster osseointegration and anchoring. Therefore, herein we have investigated the surface functionalization, biocompatibility, and effect of cellulose-nanodiamond conjugates on osteoblast proliferation and differentiation. Cellulose nanocrystals (CNC) were aminated through a 3aminopropyltriethyoxysilane (APTES) silylation, while nanodiamonds (ND) were treated with a strong acid oxidation reflux, as to produce carboxyl groups on the surface. Thereafter, the two products were covalently joined through an amide linkage, using a common bioconjugation reaction. Human fetal osteoblastic cells (hFOB) were seeded for 7 days to investigate the in vitro performance of the cellulose-nanodiamond conjugates. By employing immunocytochemistry, the bone matrix expression of osteocalcin (OC) and bone sialoprotein (BSP) was analyzed, demonstrating the viability and capacity of osteoblasts to proliferate and differentiate on the developed composite. These results suggest that cellulose-nanodiamond composites, which we call oxidized biocompatible interfacial nanocomposites (oBINC), have the potential to serve as a biointerface material for cell adhesion, proliferationand differentiation because of their osteoconductive properties and biocompatibility; furthermore, they show promising applications for bone tissue regeneration.