Nano LIFE

This study provides a detailed investigation into the chemical grafting of multiwalled carbon nanotubes (MWNTs) with starch at various concentrations and reaction temperatures. Utilizing Raman spectroscopy and Fourier-transform infrared spectroscopy (FTIR), we identified structural defects in the MWNTs and characterized the functional groups introduced by the grafting process. Differential scanning calorimetry (DSC) and thermogravimetric analysis (TGA) deepened our understanding of the interactions between starch and MWNTs, and quantified the polysaccharide content. Transmission electron microscopy (TEM) unveiled nanostructures arising from the interplay between MWNTs and starch molecules. Our findings highlight the potential of starch-grafted MWNTs for applications in nanotechnology and nanomedicine, positioning them as a promising material for targeted drug delivery and tissue engineering, aligning with Nano LIFE’s multidisciplinary goals in life sciences, nanosciences and nanomedicine.

In this study, silver nanoparticles (AgNPs) were biosynthesized from a crude leaf extract of Rhizophora mucronata. The initial phytochemical analysis of the sample revealed the presence of tannins, steroids, terpenoids, saponins and flavonoids which contribute to the reduction and stabilization of silver ions during the synthesis process. Characterization techniques, including FTIR, UV–Vis spectroscopy, SEM and EDS, confirmed the successful synthesis of AgNPs with distinctive properties. The UV–Vis spectra exhibited an absorption peak around 420 nm, characteristic of AgNPs. SEM images revealed the crystal nature of the nanoparticles, indicating structural stability. The agar well-diffusion method was employed to determine the zone of inhibition against different pathogens. The leaf extract demonstrated the highest antibacterial potential, with substantial zones of inhibition observed against all tested pathogens. The potent anti-inflammatory activity showed the minimum and maximum inhibition of protein denaturation at concentration of 25$\mu$g/mL and 100$\mu$g/mL are 28% and 69%, respectively. The silver nanoparticles demonstrated anti-inflammatory properties by inhibiting protein denaturation, suggesting their potential therapeutic applications. The mangrove R. mucronata leaf extract decided to be a favorable reducing agent for the biological synthesis of silver nanoparticles with potent antimicrobial activity.

Hybrid Ultraviolet photodetector (UVPD) was fabricated by depositing reduced graphene oxide on zinc oxide nanorods (ZnO NRs) array-coated FTO glass. Structural and optical properties of ZnO NRs were studied using TEM, SEM, XRD and UV–Vis spectroscopy. Graphene oxide (GO) sheets were synthesized from graphite powder using the modified Hummer’s method. rGO films were obtained after illuminating the GO in UV radiation. The formation of rGO and GO films was studied using AFM surface topography and UV–Vis spectroscopy. External quantum efficiency (EQE), responsivity and transient response of rGO/ZnO NR-based UV photodetector were studied in detail. The photodetector device shows very high EQE ($\sim$45 257%) and responsivity ($R$$\sim$130 A/W).

Inflammation is part of the host’s normal response to various harmful stimuli, including chemical exposure, tissue damage, infection, or contact with bacterial components, such as lipopolysaccharide (LPS); however, excessive inflammation leads to various acute and chronic human diseases. Macrophages contribute to the inflammatory process by secreting inflammatory mediators, such as prostaglandin E2 (PGE2) and nitric oxide (NO), as well as proinflammatory cytokines such as IL-1$\beta$, TNF-$\alpha$ and IL-6 and the excess of these mediators can be harmful to tissues and organisms. The RAW 264.7 murine macrophage cell line treated with LPS is a commonly used in vitro model for assessing anti-inflammatory efficacy. The base of conventional inflammation therapy is the use of steroidal and nonsteroidal anti-inflammatory medications, both of which have significant adverse effects. Therefore, finding new sources of less hazardous treatments is imperative. The anti-inflammatory qualities of bioactive lipids from crude extracts of the green alga Cladophora were investigated using ethanol and hexane-ether as two distinct solvents. As a result, the total lipid concentration of the hexane-ether extraction was higher, so the unsaturated fatty acids (UFAs) were extracted from this sample by the methanol-solvent crystallization technique at low temperatures. The presence of various fatty acids and their percentage purity were determined by gas chromatography (GC). After the elimination of 49.11% of the saturated fatty acids, the spontaneous nanoemulsification approach was applied to improve the stability and functionalization of the fatty acids. The nanoemulsion particles’ size, distribution, and stability were evaluated using a Zetasizer system. The mean particle size and zeta potential value were 194.3 nm and −25.8 mV, respectively. Finally, the MTT (thiazolyl blue tetrazolium bromide) assay was used to determine the toxicity of the extracted bioactive lipids in the macrophage cell line RAW264.7 for 24 h, and the results showed an increase in the viability of cells treated with UFAs after encapsulation. The IC${}_{50}$ values calculated from the MTT assay results for each formulation and the anti-inflammatory effects of each formulation (at 1/3 IC${}_{50}$ value) were determined in LPS-stimulated RAW 264.7 macrophages by performing nitric oxide (NO) and cytokine enzyme-linked immunosorbent assays. Nanoemulsions of polyunsaturated fatty acids inhibited the production of NO and interleukin 6, which may be promising candidates for biological and medical applications to combat inflammation.

Dental adhesive materials play a crucial role in modern dentistry, enabling the bonding of restorative materials to tooth structures. However, concerns about conventional adhesive agents’ potential toxicities and adverse effects have been raised. This has sparked interest in exploring alternative and environmentally friendly materials for dental applications. Hemidesmus indicus commonly known as Indian sarsaparilla, used historically in Ayurvedic medicine, has gained attention in nanotechnology for functionalizing nanoparticles. The primary objective of this study is to develop biogenic titanium oxide nanoparticles (H-TiO₂NPs) using Hemidesmus indicus as a natural reducing agent and further coated with curcumin, specifically for dental adhesive material applications. The nanoparticles were prepared using the green synthesis method and characterized by various techniques. The biocompatibility and bioactivity of the nanoparticles were assessed using multiple assays. The nanoparticles synthesized using root extract and capped with curcumin showed maximum absorbance at 302 nm and 498 nm in the UV spectra. The presence of characteristic peaks of curcumin in the fingerprint region of FTIR spectra reveals the capping of curcumin on TiO₂ NPs. The monoclinic structure of the nanoparticles was displayed in the XRD pattern. The SEM micrograph of uncoated and coated TiO₂ NPs exhibits spherical morphology with a size range of around 100-140 nm. Further, the EDAX of HCTN showed the elemental composition of 43.7% oxygen, 33.4% carbon and 22.8% Titanium. The biocompatibility studies of HCTN towards peripheral blood mononuclear cells (PBMCs) and erythrocytes have proved its nontoxic properties. In vitro,bioactivity studies revealed that HCTN exhibited significant antibacterial and anti-inflammatory activity, as evidenced by the inhibition of protein denaturation. The demonstrated bioactivities make them potential candidates for dental adhesive material applications. The results highlighted the potential of HCTN as a promising alternative for dental adhesive materials, offering anti-inflammatory and antimicrobial properties. This study contributes to exploring eco-friendly and biocompatible materials for use in adhesive dentistry. However, further in-depth analysis is necessary to fully understand their efficacy, safety and long-term performance in dental applications.