Search

The recent rate of the expansion of graphene nanomaterials requires appropriate toxicological assessment for biomedical usage. The toxicity of graphene and its composites is a major hurdle. Here, we report the effects of reduced graphene oxide nanocomposites on mouse fibroblast (NCTC-929) cells with the aim for futuristic biomedical applications of our synthesized material such as wearable device. The rGO was prepared by modified Hummer’s method and conjugated in comparison with carbon nanotubes (CNT), silver nanoparticles, zinc oxide particles and polyurethane to form nanocomposites. The as-prepared nanocomposites were characterized using X-ray diffraction, Raman spectroscopy, transmission electron microscope, field emission scanning electron microscopy and EDX analysis. As expected, most of our purified nanocomposites did not show any cytotoxicity on NCTC-929 cells when cultured with different doses of the samples. The nanomaterials were biocompatible and the cells displayed a viability of 80% and more. However, the nanocomposites that were autoclaved prior to testing were toxic. The materials with ZnO conjugation showed a dose dependent toxicity. The composites that had CNTs conjugated with rGO (rGO3C) were toxic than compared to the rGO-CNT conjugated with silver nanoparticles (rGO6CAgNP and rGO3CAgNP). When these nanomaterials are explored for several other applications in vivo, their biocompatibility is a major factor to be considered.

Development of green technique for the fabrication of noble metal nanoparticles is of great importance in order to avoid the usage of toxic chemicals. In this strategy, gold nanoparticles (AuNPs) are synthesized at room temperature by using Camellia japonicaleaf extract under room temperature. The successful formation of AuNPs was confirmed by various spectroscopic techniques including UV, FTIR, XRD and SEM studies. The resulting antimicrobial activity of the synthesized AuNPs stabilized in C. japonicais tested against seven different microbial strains such as Bacillus subtilis, Staphylococcus aureus, Streptococcus faecalis, Klebsiella pneumoniae, Pseudomonas aeruginosa, Escherichia coliand Candida albicans. The present study opens a new window for future synthesis of AuNPs viagreen technique.

The present work deals with the preparation of hybridized electrode material with electrostatic self assembly strategy for mesalamine (MES) detection. Grabbing significant abilities between the one dimensional bimetallic oxides and two dimensional nanosheets network a nanohybrid was designed. The developed cobalt stannate/reduced graphene oxide (Co2SnO4/rGO)-1D/2D heterostructure will possess improvised anisotropic electron transport, earth abundant, highly conducting, multiple actives site, higher surface area. The 1D/2D nanostructured architecture will enhance fast and mass transport during the electrochemical analysis which is more significant in MES detection. Progressive testing of Co2SnO4/rGO for structural analysis was done and highly crystalline nature was proved. The self assembled nanospheres to form nanocube like Co2SnO4strongly attached over the rGO matrix was confirmed with field emission scanning microscope and nanocube structure is more visible with high resolution transmission electron microscopy. The hierarchical highly electroactive material establishes lower detection limit at 4.9 nM with sensitivity about 8.57 μA μM-1cm-2. The interfacial area of nanocomposite with higher conducting channels to improve the interactions with MES resulted with enhanced selectivity. The practical analysis in environmental, pharmaceutical and biological fluids (human urine and serum) showed good recovery. The Co2SnO4/rGO will be more prominent and significant as electrode material in electrochemical sensing.

In the present work, multiple applications of natural clay loaded Samarium molybdate for photodegradation, sensing and antibacterial activity were analyzed. The clay-based materials have attracted great attention as they show good application prospects for environmental remediation. We developed natural clay loaded Sm2MoO6(CSm2MoO6) nanocomposite by hydrothermally and characterized by XRD, SEM, HR-TEM, FT-IR and optical studies. XRD pattern of CSm2MoO6exhibits peaks at 19.60, 27.80, 35.60 and 62.40 corresponding to clay and Sm2MoO6peaks clearly indicating the formation of natural clay conjugated with Sm2MoO6. SEM image of the natural clay doped CSm2MoO6nanoparticle shows a homogeneous distribution of spherical Sm2MoO6on nanoflakes of clay material. HR-TEM images reveal that the average particle size is 50 nm. Loading of natural clay material increased the visible absorption of Sm2MoO6by reducing the band gap from 3.82 to 2.39 eV. Decomposition of 20 ppm of Metronidazole (MNZ) was 95% with 60 mg of CSm2MoO6in 100 min of visible light illumination. Hydroxyl radicals played the main role for photodegradation of MNZ. Electrochemical analysis revealed that the oxidation peak current of 4-aminophenol has increased with a high potential at pH 6.0 and CSm2MoO 6/SPCE electrode has an advantage of low detection limit of 0.005 μM and a long linear range of 2949.72 μM with a sensitivity of 5.29301 μM. The synthesized nanocomposite has a significant bactericidal activity against Bacillus subtilis, Staphylococcus aureus, Proteus mirabilis, Bacteroides fragilis, E. coliand Candida albicans. These results make this green catalyst potential for multiple applications.