The advanced development of cell carriers for regenerative medicine and cell therapy demands materials able to sustain cell viability prior to their delivery to the target tissue, ability which can be controlled via the shape/size and degradability of the matrix. TEMPO-oxidized nanofibrillar cellulose (ToNFC) macromolecules are negatively charged and therefore can be easily formulated by ionotropic gelation into beads of varying sizes that can release their payload through an erosion-controlled process. We report here for the first time on the preparation of ToNFC beads via ionic gelation using CaCl2 and on their loading with OSTEO-1 rat bone cells, with a view to examine their capacity of sustaining the cell viability and of releasing the bone cells in a controlled manner. The initial results obtained demonstrate that ToNFC is able to protect the OSTEO-1 cells and to maintain their viability for at least two weeks; following gradual disintegration of the beads, a significant cell release and subsequent proliferation was observed after 7 days. These results indicate the considerable potential of nanofibrillar cellulose (ToNFC) for applications in cell therapy and regenerative medicine.

In this study fabrication and characterization of transparent nanostructured composite films based on cellulose triacetate (CTA) and poly(ethylene oxide)-b-poly(propylene oxide)-b-poly(ethylene oxide) (EPE) triblock copolymer were presented. The effect of the addition of EPE triblock copolymer on the thermal stability, morphology, and mechanical properties of cellulose triacetate films was investigated. The triblock EPE was chosen since PEO blocks interact favorably with CTA, whereas, PPO blocks remain immiscible which provokes a microphase separation. This allows to obtain EPE/CTA composite films with ordered microphase-separated structures where PPO spherical microdomains are well-dispersed in PEO/CTA matrix by simple solvent-evaporation process. During this process, PEO block chains selectively interact with CTA by strong interpolymer hydrogen-bonding while PPO block microseparated. The addition even 40wt% of EPE leads to nanostructured EPE/CTA composite. The cytotoxicity assay of CTA and EPE/CTA composite films confirm non-toxic character of designed transparent nanostructured composites based on sustainable matrices.

In this work we explored the fabrication of flexible and transparent hybrids of silk fibroin (SF) and epoxy-modified siloxane for photonic applications. It is well-known that regenerated SF solutions can form free-standing films with high transparency. Although SF has a restricted number of chemically reactive side groups, the main issues of as-cast pristine SF films regard the high solubility into aqueous media, brittleness, and low thermal stability. The design of SF films with enhanced functionality but high transparency triggers new opportunities on a broader range of applications in biophotonics. Here we present a simple, functional, yet remarkably versatile hybrid material derived from silica sol-gel process based on SF protein and (3-glycidyloxypropyl)trimethoxysilane (GPTMS), an organically modified silicon-alkoxide owning a reactive terminal epoxy group. Specifically, we investigated the effect of the addition of GPTMS into SF solutions on the processability, morphology, crystallinity, and mechanical and optical properties of the resulting hybrid films. Highly transparent (ca. 90%) and flexible free-standing hybrid films were achieved. Cell viability assays revealed that the hybrid films are noncytotoxic to rat osteoblast cells even at high GPTMS content (up to 70 wt %). The hybrid films showed enhanced thermal stability and were rich in organic (epoxy) and inorganic (silanol) functional groups according to the content of GPTMS. We also evaluated the successful preparation of high-quality optical red emissive SF hybrid films by loading YVO:Eu nanoparticles at low concentration (<5 wt %). A meaningful description of the hybrid film structure is reported from the combination of scanning electron and atomic force microscopies, vibrational spectroscopy, solid-state NMR, and X-ray diffraction analyses.

Aspects related to micronutrients management are still poorly studied and need to be clarified to guarantee sustainable production. In this way, the study aimed to evaluate boron (B) fertilization effects on nutrition and production of common beans. The parameters measured were relative chlorophyll index, dry mass, boron transport, utilization and absorption efficiencies, B content, and B accumulation in plant tissues. The study showed that the dry mass production was negatively affected by B application, with linear dry mass decrease following the increase of B doses. Accordingly, it was found that the common bean cultivar Esplendor presented high absorption capacity of boron, and can reach 175 mg kg −1. However, the high absorption caused phytotoxicity and reduced dry matter production by up to 30%, reflecting the efficiency of boron use by the plant, which was reduced in up to 75%.

Autologous fibrin matrices derived from the Leukocyte and Platelet Rich Plasma (L-PRP) and Leukocyte and Platelet Rich Fibrin (L-PRF) techniques present great potential to act as a bioactive scaffold in regenerative medicine, contributing to the maintenance of cell viability, proliferation stimulus and differentiation. In contrast, there are few studies that characterize the bioactive potential of these fibrin scaffolds by considering the process of production. The objective of this work was to characterize the intrinsic potential of maintaining cell viability of different fibrin scaffolds containing platelets and leukocytes. In order to achieve that, blood samples from a volunteer were collected and processed to obtain fibrin clots using the suggested techniques. To characterize the potential for in vitro viability, mesenchymal stem cells from human infrapatellar fat were used. The scaffolds were cellularized (1x10 5 cells/scaffolds) and maintained for 5 and 10 days under culture conditions with Dulbecco's Modified Eagle Medium, without addition of fetal bovine serum, and subsequently subjected to analyses by Fourrier transform infra-red spectroscopy, circular dichroism and fluorescence microscopy. The results demonstrated distinct intrinsic potential viability between the scaffolds, and L-PRP was responsible for promoting higher levels of viability in both periods of analysis. No viable cells were identified in the fibrin matrix used as controls. These results allow us to conclude that both fibrin substrates have presented intrinsic potential for maintaining cell viability, with superior potential exhibited by L-PRP scaffold, and represent promising alternatives for use as bioactive supports in musculoskeletal regenerative medicine.