Purpose: Tissue engineering aims to recreate natural cellular environments to facilitate tissue regeneration. Gelatin methacrylate (GelMA) is widely utilized for its biocompatibility, ability to support cell adhesion and proliferation, and adjustable mechanical characteristics. This study developed a GelMA and graphene bioink platform at concentrations of 1, 1.5, and 2 mg/mL to enhance scaffold properties for tissue engineering applications. Patients and Methods: Graphene was incorporated into GelMA matrices to improve mechanical strength and electrical conductivity of the bioinks. The compressive strength and thermal stability of the resulting GelMA/graphene scaffolds were assessed through DSC analysis and mechanical testing. Cytotoxicity assays were conducted to determine cell survival rates. Cryoprinting at − 30°C was employed to preserve scaffold structure and function. The chorioallantoic membrane (CAM) assay was used to evaluate biocompatibility and angiogenic potential. Results: The integration of graphene significantly amplified the compressive strength and thermal stability of GelMA scaffolds. Cytotoxicity assays indicated robust cell survival rates of 90%, confirming the biocompatibility of the developed materials. Cryoprinting effectively preserved scaffold integrity and functionality. The CAM assay validated the biocompatibility and angiogenic potential, demonstrating substantial vascularization upon scaffold implantation onto chick embryo CAM. Conclusion: Integrating graphene into GelMA hydrogels, coupled with low-temperature 3D printing, represents a potent strategy for enhancing scaffold fabrication. The resultant GelMA/graphene scaffolds exhibit superior mechanical properties, biocompatibility, and pro-vascularization capabilities, making them highly suitable for diverse tissue engineering and regenerative medicine applications.

In this work, Coca-Cola^® bottles were reused as a PET polymer (rPET) source to produce electrospun polymeric nanofibers. The nanofibers were electrospun from polymer solutions with different concentrations of reduced graphene oxide (rGO) incorporated for applications in somatosensory electrical stimulation. The rPET/rGO nanofiber mats were characterized by SEM, TEM, Raman, DSC, TGA, and DMA and the results showed that the incorporation of rGO in electrospun rPET fibers produced rPET/rGO composites. The rPET/rGO composites were then evaluated for possible application as dry electrodes. Moreover, with a preliminary test of numerous volunteers, the rPET/rGO dry electrode showed promising results. The rPET/rGO electrodes showed good performance and applicability to make dry electrodes, and these have applications as dry or wearable electrodes to produce electrochemical sensors.

Background: The 3D printing of macro- and mesoporous biomimetic grafts composed of polycaprolactone (PCL) infused with nanosized synthetic smectic clay is a promising innovation in biomaterials for bone tissue engineering (BTE). The main challenge lies in achieving a uniform distribution of nanoceramics across low to high concentrations within the polymer matrix while preserving mechanical properties and biological performance essential for successful osseointegration. Methods: This study utilized 3D printing to fabricate PCL scaffolds enriched with nanosized synthetic smectic clay (LAP) to evaluate its effects on structural, chemical, thermal, mechanical, and degradative properties, with a focus on in vitro biological performance and non-toxicity. Scaffolds were created with varying proportions of PCL and LAP. Comprehensive characterization included scanning electron microscopy (SEM), X-ray diffraction (XRD), thermogravimetric analysis (TGA), Fourier-transform infrared spectroscopy (FTIR), mechanical testing, swelling analysis, and degradation studies. Biological performance was assessed through MTT assays (cell viability), alkaline phosphatase activity, histological analysis, and Raman spectroscopy, highlighting the scaffolds’ biocompatibility and potential applications in regenerative medicine. Results: The developed inks demonstrated excellent injectability, and the 3D-printed PCL/LAP scaffolds exhibited a microporous and rough structure, good structural fidelity, low degradability, thermal stability, and sufficient mechanical strength across all formulations. Intrinsic properties of the scaffolds revealed no cytotoxicity while enhancing bioactivity and promoting in vitro mineralization when cultured with mesenchymal stem cells in all analyzed groups. Notably, the high concentration of LAP within the PCL matrices did not induce in vitro cytotoxicity but rather stimulated in vitro mineralization and differentiation. Conclusion: This study demonstrated the feasibility of 3D printing PCL/LAP scaffolds with high concentrations of nanoceramics. Both in vitro and in vivo assays validated the regenerative potential of these scaffolds, emphasizing their efficacy as a promising approach for developing advanced biomimetic grafts.

Amburana cearensis tree is used in various applications, from artisanal to pharmaceutical use. However, the gum extracted from its exudate has not yet been investigated. This study aimed to the physicochemical and structural characterization of Amburana cearensis Gum (AcG) by elemental, rheological, and thermal analyses, X-ray diffraction (XRD), high-Performance Liquid Chromatography (HPLC), Gel Permeation Chromatography (GPC), Infrared Spectroscopy (FTIR), UV-Vis spectroscopy and nuclear magnetic resonance (NMR). Additionally, a hemolytic assay was performed to evaluate the biocompatibility of AcG using human erythrocytes. The results showed that AcG consists of β-D-Galactopyranose monomers linked by glycosidic bonds (1→3). At the same time, the side chains exhibit β-Galactopyranose (1→6) and α-L-Arabinofuranoside (1→3,6) monomers as non-reducing terminals, whose biocompatibility was excellent in the model used. AcG was described for the first time as a biopolymer that could have broad applications in the pharmaceutical and cosmetic industries, justifying the interest in further studies about AcG applications.

O objetivo dessa pesquisa visa verificar o comportamento de um biofertilizante sólido produzido a partir da mistura de cera de carnaúba do tipo “A” aquecida ate seu ponto de fusão seguida do acréscimo de norbixina por meio de caracterizações físico-químicas, toxicológica e de aplicação. As caracterizações físico-químicas realizadas foram DRX, FTIR, TGA, DSC. O ensaio de toxicidade com Allium cepa foi realizado como teste biológico e, o ensaio de aplicação do biofertilizante em solo humoso. Os resultados obtidos revelaram que ocorreu diminuição da cristalinidade do biofertilizante de acordo com o aumento da quantidade de norbixina. As bandas de absorção mostraram que a norbixina contém grupos funcionais capazes de realizar interações intermoleculares com a cadeia da cera de carnaúba. Não houve alteração na estabilidade térmica do biofertilizante, como também, não ocorreu alteração da temperatura de fusão entre a cera e o biofertilizante produzido. O biofertilizante não revelou toxicidade nas proporções de norbixina adicionada. Porém, a aplicação do biofertilizante em solo humoso, torna-se necessário a realização de ensaios com maior duração, ou seja, com tempo superior a 10 dias.

During the final review of our manuscript