A comprehensive review on Moringa oleifera nanoparticles: importance of polyphenols in nanoparticle synthesis, nanoparticle efficacy and their applications.

Moringa oleifera is one of the popular functional foods that has been tremendously exploited for synthesis of a vast majority of metal nanoparticles (NPs). The diverse secondary metabolites present in this plant turn it into a green tool for synthesis of different NPs with various biological activities. In this review, we discussed different types of NPs including silver, gold, titanium oxide, iron oxide, and zinc oxide NPs produced from the extract of different parts of M. oleifera. Different parts of M. oleifera take a role as the reducing, stabilizing, capping agent, and depending on the source of extract, the color of solution changes within NP synthesis. We highlighted the role of polyphenols in the synthesis of NPs among major constituents of M. oleifera extract. The different synthesis methods that could lead to the formation of various sizes and shapes of NPs and play crucial role in biomedical application were critically discussed. We further debated the mechanism of interaction of NPs with various sizes and shapes with the cells, and further their clearance from the body. The application of NPs made from M. oleifera extract as anticancer, antimicrobial, wound healing, and water treatment agent were also discussed. Small NPs show better antimicrobial activity, while they can be easily cleared from the body through the kidney. In contrast, large NPs are taken by the mono nuclear phagocyte system (MPS) cells. In case of shape, the NPs with spherical shape penetrate into the bacteria, and show stronger antibacterial activity compared to the NPs with other shapes. Finally, this review aims to correlate the key characteristics of NPs made from M. oleifera extract, such as size and shape, to their interactions with the cells for designing and engineering them for bio-applications and especially for therapeutic purposes.

Synthesis of antibacterial hydroxypropyl methylcellulose and silver nanoparticle biocomposites via solution plasma using silver electrodes.

The biocomposites of hydroxypropyl methylcellulose (HPMC)/silver nanoparticles (AgNPs) were synthesized using the solution plasma process (SPP). HPMC/AgNPs were synthesized in 1-5 % HPMC solutions using silver electrodes. UV-Vis spectroscopy showed a peak near 400 nm and the peak increased as the concentration of HPMC and discharge time increased. FTIR analysis indicated no change in the chemical structure of the HPMC based biocomposites. Spherical shaped AgNPs with size ranges about 2-18 nm and well dispersed in the porous HPMC matrices with fringed edges were observed by TEM and SEM/EDS analyses. The synthesized biocomposites were found to be thermo-stable by TGA analysis. The inhibition zones of bacterial growth formed by the HPMC/AgNPs biocomposites were in the range of 8-14.3 mm; minimal inhibition concentrations, in the range of 10-15 µg·mL-1 for Gram-negative bacteria; 25-30 µg·mL-1 for Gram-positive bacteria. The biocomposites were non-toxic to the HEK293 cells up to 125 µg·mL-1. The results indicated that the synthesis of antibacterial agents in the HPMC matrix using silver electrodes via SPP would be an efficient and safe way for the development of biopolymer based antimicrobials and wound healing biomaterials.

Synthesis and Characterization of Tween-20 Capped Biosynthesized Silver Nanoparticles for Anticancer and Antimicrobial Property.

The Vitrus vinifera fruit extract was used to make silver nanoparticles (AgNPs) utilizing a green chemical technique. The biosynthesized Tween-20/Vitrus vinifera-AgNPs were observed by UV-Vis spectrophotometry. Fourier transform infrared spectroscopy, scanning transmission electron microscopy, selected area electron diffraction, and energy-dispersive X-ray spectroscopy were used to characterize the physiochemical properties. The spherical form of AgNPs was confirmed by transmission electron microscopy. The peaks in the Tween-20/Vitrus vinifera-AgNPs have an average crystallite size that is found to be 46 nm according to powder X-ray diffraction examination. Biosynthesized AgNPs had a significant effect on bone osteosarcoma MG63 cells with 55% inhibition, respectively, using MTT assay. The effective dangerous concentration of Tween-20/Vitrus vinifera with AgNP nanoparticles was less harmful to MG63 cells. The results of antibacterial activity showed that Tween-20/Vitrus vinifera-AgNPs effectively inhibited Eggerthella lenta and Staphylococcus epidermis bacteria.

Unveiling the potentials of biocompatible silver nanoparticles on human lung carcinoma A549 cells and Helicobacter pylori.

Silver nanoparticles (AgNPs) are gaining importance in health and environment. This study synthesized AgNPs using the bark extract of a plant, Toxicodendron vernicifluum (Tv) as confirmed by a absorption peak at 420 nm corresponding to the Plasmon resonance of AgNPs. The AgNPs were spherical, oval-shaped with size range of 2-40 nm as evident by field emission transmission electron microscopy (FE-TEM) and particle size analysis (PSA). The particles formed were crystalline by the presence of (111), (220) and (200) planes, as revealed by X ray diffraction (XRD) and energy dispersive spectroscopy (EDS). The presence of amine, amide, phenolic, and alcoholic aromatics derived from Tv extract was found to be capping and or reducing agents as evident by Fourier-transform infrared spectroscopy (FTIR) spectra. The Tv-AgNPs were observed to be biocompatible to chick embryonic and NIH3T3 cells at various concentrations. Interestingly, Tv-AgNPs at the concentration of 320 µg. mL-1 induced 82.5% of cell death in human lung cancer, A549 cells and further 95% of cell death with annexin V FITC/PI based apoptosis. The Tv-AgNPs selectively targeted and damaged the cancer cells through ROS generation. The Tv-AgNPs displayed minimal inhibitory concentration (MIC) of 8.12 µg.mL-1 and 18.14 µg.mL-1 against STEC and H. pylori respectively. This multi-potent property of Tv-AgNPs was due to shape and size specific property that facilitated easy penetration into the bacterial and cancer cells for targeted therapy.

One pot synthesis and anti-biofilm potential of copper nanoparticles (CuNPs) against clinical strains of Pseudomonas aeruginosa.

Pseudomonas aeruginosa, an opportunistic pathogen frequently associated with nosocomial infections, is emerging as a serious threat due to its resistance to broad spectrum antimicrobials. The biofilm mode of growth confers resistance to antibiotics and novel anti-biofilm agents are urgently needed. Nanoparticle based treatments and therapies have been of recent interest because of their versatile applications. This study investigates the anti-biofilm activity of copper nanoparticles (CuNPs) synthesized by the one pot method against P. aeruginosa. Standard physical techniques including UV-visible and Fourier transform infrared spectroscopy, X-ray diffraction and transmission electron microscopy were used to characterize the synthesized CuNPs. CuNP treatments at 100 ng ml(-1) resulted in a 94, 89 and 92% reduction in biofilm, cell surface hydrophobicity and exopolysaccharides respectively, without bactericidal activity. Evidence of biofilm inhibition was also seen with light and confocal microscope analysis. This study highlights the anti-biofilm potential of CuNPs, which could be utilized as coating agents on surgical devices and medical implants to manage biofilm associated infections.

An investigation on the cytotoxicity and caspase-mediated apoptotic effect of biologically synthesized silver nanoparticles using Podophyllum hexandrum on human cervical carcinoma cells.

Now-a-days synthesis and characterization of silver nanoparticles (AgNPs) through biological entity is quite interesting to employ AgNPs for various biomedical applications in general and treatment of cancer in particular. This paper presents the green synthesis of AgNPs using leaf extract of Podophyllum hexandrum Royle and optimized with various parameters such as pH, temperature, reaction time, volume of extract and metal ion concentration for synthesis of AgNPs. TEM, XRD and FTIR were adopted for characterization. The synthesized nanoparticles were found to be spherical shaped with average size of 14 nm. Effects of AgNPs were analyzed against human cervical carcinoma cells by MTT Assay, quantification of ROS, RT-PCR and western blotting techniques. The overall result indicates that AgNPs can selectively inhibit the cellular mechanism of HeLa by DNA damage and caspase mediated cell death. This biological procedure for synthesis of AgNPs and selective inhibition of cancerous cells gives an alternative avenue to treat human cancer effectively.