Nano LIFE

Nerve repair and regeneration are still challenging issues in the world, mainly due to the complex anatomic structure and limited regeneration ability of natural nerves. Tissue engineering provides a structure and function similar to nerve tissue through scaffold materials, seed cells, and active factors, which is a promising method to treat nerve injury. Gelatin methacrylate (GelMA) hydrogel is a kind of gelatin modified by methacrylamide, which possesses adjustable mechanical properties, convenient processability, and excellent biocompatibility, has been widely used in nerve tissue engineering. In this paper, the research progress of GelMA-based hydrogel in nerve repair and regeneration in recent five years is reviewed, with emphasis on the advanced manufacturing technologies of three-dimensional (3D) GelMA scaffold and the application systems that can effectively promote nerve repair and regeneration. We also evaluated the challenges and prospects of GelMA-based hydrogels in the field of nerve repair and regeneration, which is of guiding significance to the research of nerve tissue engineering.

This work includes the use of leaves of Mitragyna parvifolia for green synthesis of ${\mathrm{\text{Fe}}}_2{\mathrm{\text{O}}}_3$ nanoparticles (${\mathrm{\text{Fe}}}_2{\mathrm{\text{O}}}_3$ NPs), which offers a sustainable eco-friendly approach. Characterization of synthesized ${\mathrm{\text{Fe}}}_2{\mathrm{\text{O}}}_3$ NPs was done by UV-visible, FTIR spectroscopy, XRD and FESEM studies. FTIR exhibited the existence of Fe-O, O–H and COO–Fe stretching owing to the occurrence of the carboxylic group. FESEM analysis revealed that the average size of ${\mathrm{\text{Fe}}}_2{\mathrm{\text{O}}}_3$ NPs was 92 nm, which varies in their shape. The study also includes the determination of antibacterial, in vitro antioxidant and immunomodulatory efficacy of synthesized ${\mathrm{\text{Fe}}}_2{\mathrm{\text{O}}}_3$ NPs. Results suggested that ${\mathrm{\text{Fe}}}_2{\mathrm{\text{O}}}_3$ NPs exhibit potent antibacterial efficacy against B. subtilis and S. aureus, gram-positive as well as E. coli and P. aureginosa, gram-negative bacterial strains used in this study. The study exhibited significant ($p$ < 0.01) in vitro antioxidant and immunomodulatory potential of synthesized ${\mathrm{\text{Fe}}}_2{\mathrm{\text{O}}}_3$ NPs against concanavalin-A activated Wistar albino rat’s splenocytes. The green synthesized ${\mathrm{\text{Fe}}}_2{\mathrm{\text{O}}}_3$ NPs using M. parvifolia leaves may offer a novel approach in the medicinal and immunological field to overcome oxidative stress as well as enhance immune responses for potential health benefits of human beings.

Nanoparticles (NPs) are synthesized in different methods such as physical or chemical which are costly and harmful to the environment. However, green synthesis is a cost-effective and environment-friendly NPs synthesis approach. Green-synthesized NPs are highly effective against various bacterial strains. Zirconium dioxide nanoparticles (${\mathrm{\text{ZrO}}}_2\mathrm{\text{NPs}}$) have been synthesized in this research using a cost-effective green synthesis approach for improved antimicrobial activity. For the synthesis of the NPs, Alocasia indica has been used as a reducing agent. The extract of Alocasia indica was prepared and reacted with the light solution of ZrOCl₂ ⋅ 8H₂O. The successful formation of ${\mathrm{\text{ZrO}}}_2\mathrm{\text{NPs}}$ was confirmed by the color change in the solution. Some analytical techniques, including Ultraviolet-visible (UV) spectroscopy, Fourier Transformed Infrared Spectroscopy (FTIR), Scanning Electron Microscopy (SEM), Transmission Electron Microscopy (TEM), Energy Dispersive X-ray (EDX), X-ray diffraction (XRD), and bacterial inhibition analyses have been performed to analyze the performance of the synthesized NPs. The peaks formed in the UV analysis also confirmed the formation of NPs in the solution. The presence of various functional groups in the synthesized ${\mathrm{\text{ZrO}}}_2\mathrm{\text{NPs}}$ has been confirmed by the FTIR analysis. TEM analysis revealed that the synthesized NPs were almost circular. The formation of peak confirmed the crystalline structure of the NPs. Impressively; a 99.99% bacterial inhibition rate was obtained against the gram-positive bacteria strain. The synthesized ${\mathrm{\text{ZrO}}}_2\mathrm{\text{NPs}}$ have great potential for biomedical applications such as medicine and implants for its excellent antimicrobial applications.

Because of the exceptional qualities, nano-hydroxyapatites, or n-HA, are excellent materials for diverse applications. It is simple and convenient to synthesize from various natural ingredients. The synthesis of n-HA from eggshells, a typical domestic waste product in the neighborhood, was the primary goal of this study project. This synthesis of n-HA was performed using ammonia and orthophosphoric acid as chemical reagents. The synthesized n-HA have been characterized by UV (Ultraviolet), FTIR (Fourier Transformed Infrared Spectroscopy), SEM (Scanning Electron Microscopy), TEM (Transmission Electron Microscopy), and XRD (X-ray diffraction) analysis. The peak formed by the UV analysis verified the successful formation of n-HA in the solution. The bandgap has been determined through additional research on the UV data. The SEM and TEM images show the size and form of the synthesized n-HA. Based on TEM observations, the synthesized n-HA has a size in the range of 10 to 40 nm. The peak ensures the n-HA’s crystallinity that the XRD analysis produced. The obtained crystallinity was 74%.

Streptomycin was chosen as the test species, and MgO@graphene nanocomposites were created and assessed for their catalytic activity towards the breakdown of 4-NP. As a new catalyst with strong catalytic activity and good stability, MgO@graphene was used. It was discovered that this catalyst’s catalytic activity was much increased in an acidic environment. It is suggested that the degradation mechanism is caused by MgO@graphene nanocomposites reacting with dissolved oxygen. This further demonstrates the obvious significance of graphene in serving as the MgO nanocatalyst’s support. XRD results indicated that the majority of G species in MgO@ (0.25 g) G more strongly interacted with the MgO surface. The doped catalyst MgO@ (0.25 g) G reached its steady state activity faster than the other catalysts. The degree of MgO@G interaction decreased in the following S₄ > S${}_{\text{mix}}$ > S${}_2$ > S${}_3$ > S${}_1$ > S₅ > S${}_6$ > S${}_{\text{o}}$. High degradation rate constants were found, and the amounts of streptomycin and 4-nitrophenol vary exponentially over time. It was demonstrated that, in most situations, the pseudo-first- order equation fits the degradation kinetics. Hence, in degrading systems, MgO NPs@Graphene nanostructures are thought to be a very effective and promising catalyst.