SILVER NANOPARTICLES OF MORINGA OLEIFERA – GREEN SYNTHESIS,CHARACTERISATION AND ITS ANTIMICROBIAL EFFICACY

Abstract : The traditional medicinal plant Moringa oleifera is an integral part of the Indian diet and has notable beneficial effects in its leaves, stems, flowers, roots, bark and seeds. It has reported properties like antimicrobial, anti inflammatory, ant diabetic, anti oxidative, anti tumorogenic amongst many other properties. In the present study we have devised a new green method of synthesis of silver nanoparticles to evaluate its antimicrobial efficacy using the aqueous plant extract as the reductant as well as the stabilizer. A cold method of synthesis of silver nanoparticles using silver nitrate solution is performed. After the synthesis step, the nanoparticles are characterised using UV VIS spectroscopy, scanning electron microscopy and transmission electron microscopy. The results show the incorporation of the silver ions in the extract and also the reduction of the particle size to the nano range. The antimicrobial potential of these nanoparticles synthesized is tested against various gram positive and gram negative strains of bacteria keeping streptomycin as the standard positive control antibiotic. The antibiotic assay is performed using agar well diffusion method and comparable results are obtained in comparison to the standard antibiotic. It is seen that the nanoparticles have good antibacterial efficacy against the tested strains. Hence nanoparticles of Moringa oleifera aqueous extracts can be used as a potential alternative to traditional antibiotics using this non toxic safe way of green synthesis. Keywords: Moringa oleifera, silver nanoparticles, antimicrobia

Bioactive Silver Phosphate/Polyindole Nanocomposites

Materials capable of releasing reactive oxygen species (ROS) can display antibacterial and anticancer activity, and may also have anti-oxidant capacity if they suppress intracellular ROS (e.g. nitric oxide, NO) resulting in anti-inflammatory activity. Herein we report silver phosphate (Ag3PO4)/polyindole (Pln) nanocomposites which display antibacterial, anticancer and anti-inflammatory activity, and have therefore potential for a variety of biomedical applications

Design and Synthesis of Fluorescent Carbon Dot Polymer and Deciphering Its Electronic Structure

Herein we report the one-pot synthesis of a fluorescent polymer-like material (pCD) by exploiting ruthenium-doped carbon dots (CDs) as building blocks. The unusual spectral profiles of pCDswith double-humped periodic excitation dependent photoluminescence (EDPL), and the regular changes in their corresponding average lifetime indicate the formation of high energy donor states and low energy aggregated states due to the overlap of molecular orbitals throughout the chemically switchable π-network of CDs on polymerization. To probe the electronic distribution of pCDs, we have investigated the occurrence of photoinduced electron transfer with a model electron acceptor, menadione using transient absorption technique, corroborated with low magnetic field, followed by identification of the transient radical ions generated through electron transfer. The experimentally obtained B_(1/2) value, a measure of the hyperfine interactions present in the system, indicates the presence of highly conjugated π-electron cloud in pCDs. The mechanism of formation of pCDs and the entire experimental findings have further been investigated through molecular modeling and computational modeling. The DFT calculations demonstrated probable electronic transitions from the surface moieties of pCDs to the tethered ligands

Design and Synthesis of Fluorescent Carbon Dot Polymer and Deciphering Its Electronic Structure

Herein we report the one-pot synthesis of a fluorescent polymer-like material (pCD) by exploiting ruthenium-doped carbon dots (CDs) as building blocks. The unusual spectral profiles of pCDswith double-humped periodic excitation dependent photoluminescence (EDPL), and the regular changes in their corresponding average lifetime indicate the formation of high energy donor states and low energy aggregated states due to the overlap of molecular orbitals throughout the chemically switchable π-network of CDs on polymerization. To probe the electronic distribution of pCDs, we have investigated the occurrence of photoinduced electron transfer with a model electron acceptor, menadione using transient absorption technique, corroborated with low magnetic field, followed by identification of the transient radical ions generated through electron transfer. The experimentally obtained B_(1/2) value, a measure of the hyperfine interactions present in the system, indicates the presence of highly conjugated π-electron cloud in pCDs. The mechanism of formation of pCDs and the entire experimental findings have further been investigated through molecular modeling and computational modeling. The DFT calculations demonstrated probable electronic transitions from the surface moieties of pCDs to the tethered ligands

Ginseng used for bone tissue scaffold

696-701The scaffold based tissue engineering materialized for bone tissue therapy. Gelatin-glutaraldehyde cross linked scaffold was prepared by solvent casting -porogen leaching method. It was characterized by FTIR and SEM microphotograph analysis. Absence of peak at waves no. 1625 cm−1 in ATR-FTIR indicated formation of cross-linking. FE-SEM micrograph showed honeycomb pad like structure with high porosity. Methanolic extract of Withania somnifera (Ashwagandha) root extract induced MC3T3 E1 osteoblast cell adhesion and proliferation on porous gelatin scaffold. GC-MS analysis pointed out presence of 4-amino- 2-ethyl-3-methylquinoline, an active phyto-chemicals having tissue regeneration potential. High anti-oxidant capacity down regulates cell death mechanism by scavenging free radical. The biocompatible gelatin scaffold has RGD moiety that attune the MC3T3 E1 osteoblast cell adhesion. Withania somnifera root extract may boost up cell proliferation on scaffold. Therefore treatment with Withania somnifera root extract may be the new approaches for designing bone tissue scaffold for bone tissue therapy

Ginseng used for bone tissue scaffold

The scaffold based tissue engineering materialized for bone tissue therapy. Gelatin-glutaraldehyde cross linked scaffold was prepared by solvent casting -porogen leaching method. It was characterized by FTIR and SEM microphotograph analysis. Absence of peak at waves no. 1625 cm−1 in ATR-FTIR indicated formation of cross-linking. FE-SEM micrograph showed honeycomb pad like structure with high porosity. Methanolic extract of Withania somnifera (Ashwagandha) root extract induced MC3T3 E1 osteoblast cell adhesion and proliferation on porous gelatin scaffold. GC-MS analysis pointed out presence of 4-amino- 2-ethyl-3-methylquinoline, an active phyto-chemicals having tissue regeneration potential. High anti-oxidant capacity down regulates cell death mechanism by scavenging free radical. The biocompatible gelatin scaffold has RGD moiety that attune the MC3T3 E1 osteoblast cell adhesion. Withania somnifera root extract may boost up cell proliferation on scaffold. Therefore treatment with Withania somnifera root extract may be the new approaches for designing bone tissue scaffold for bone tissue therapy