An overview on biomedical applications of versatile silica nanoparticles, synthesized via several chemical and biological routes: A review

Synthesis and Structural Characterization of SiO2 Nanoparticles Using Extract of Gracilaria Crassa Via Green Chemistry Approach

Biologically synthesized nanoparticles via biological entities are produced with less negative impact on the environment and without expensive chemicals, which have biocompatibility and are eco-friendly. Gracilaria crassa is a well-known marine red alga that is edible and unique and is the commercial source of agar and agarose production. In this work, Gracilaria crassa-mediated SiO2 NPs were synthesized by the green synthesis method. In order to characterize the physicochemical properties of the synthesized SiO2 NPs, a variety of microscopic and spectroscopic approaches were used, including imaging with Field emission scanning electron microscopy, Energy-dispersive X-ray analysis, UV spectrophotometry, X-ray diffraction analysis, Fourier-transform infrared spectroscopy, Zeta potential, and Thermo gravimetric analysis. These results shown that Gracilaria crassa-mediated SiO2 NPs were amorphous nature, negatively charged -15.5 mV and spherical shape in size of 20-50 nm. The antioxidant capacity of synthesised SiO2 NPs was examined by 2,2-Diphenyl-1-picrylhydrazyl assay and it observed as IC50 value of 49.4 μg/mL denotes that could counteract the production of free radicals and oxidative stress. The characteristics of the synthesized Gracilara crassa-mediated SiO2 NPs suggest their application as potential antioxidant agents.

Nanomaterial strategies in wound healing: A comprehensive review of nanoparticles, nanofibres and nanosheets

Wound healing is a complex process that orchestrates the coordinated action of various cells, cytokines and growth factors. Nanotechnology offers exciting new possibilities for enhancing the healing process by providing novel materials and approaches to deliver bioactive molecules to the wound site. This article elucidates recent advancements in utilizing nanoparticles, nanofibres and nanosheets for wound healing. It comprehensively discusses the advantages and limitations of each of these materials, as well as their potential applications in various types of wounds. Each of these materials, despite sharing common properties, can exhibit distinct practical characteristics that render them particularly valuable for healing various types of wounds. In this review, our primary focus is to provide a comprehensive overview of the current state-of-the-art in applying nanoparticles, nanofibres, nanosheets and their combinations to wound healing, serving as a valuable resource to guide researchers in their appropriate utilization of these nanomaterials in wound-healing research. Further studies are necessary to gain insight into the application of this type of nanomaterials in clinical settings.

Structural Unit Determination in Silica Nanoparticles Using Infrared Micro-Reflectance Spectroscopy

A method based on infrared (IR) micro-reflectance measurements for the structural characterization of glassy nanomaterials is presented. Near-specular reflectance spectra of pressed pellets can be analyzed using a model relating the structure of silicate glasses to their dielectric response and an effective medium approximation to account for the effect of porosity. The integrated intensities of phenomenological bands attributed to Q 2 , Q 3 , and Q 4 structural units allow quantifying their relative populations. These values are in good agreement with those obtained with magic-angle spinning nuclear magnetic resonance, which serves as validation of the method and proves the feasibility of extracting quantitative information about glass structure from IR micro-reflectance experiments.

Nanoparticle-Containing Wound Dressing: Antimicrobial and Healing Effects

The dressings containing nanoparticles of metals and metal oxides are promising types of materials for wound repair. In such dressings, biocompatible and nontoxic hydrophilic polymers are used as a matrix. In the present review, we take a look at the anti-microbial effect of the nanoparticle-modified wound dressings against various microorganisms and evaluate their healing action. A detailed analysis of 31 sources published in 2021 and 2022 was performed. Furthermore, a trend for development of modern antibacterial wound-healing nanomaterials was shown as exemplified in publications starting from 2018. The review may be helpful for researchers working in the areas of biotechnology, medicine, epidemiology, material science and other fields aimed at the improvement of the quality of life.