, et al. told that Nanotechnology involves the production, manipulation and use ofmaterials ranging in size from less than a micron to that of individual atoms. Althoughnanomaterials may be synthesized using chemical approaches, it is now possible to include theuse of biological materials. In this review, we critically assess the role of microorganisms andplants in the synthesis of nanoparticles 136.Palaniselvam., et al.
The field of nanotechnology mainly encompasses with biology, physics,chemistry and material sciences and it develops novel therapeutic nanosized materials forbiomedical and pharmaceutical applications. The biological syntheses of nanoparticles are beingcarried out by different macro–microscopic organisms such as plant, bacteria, fungi, seaweedsand microalgae. The biosynthesized nanomaterials have been effectively controlling the variousendemic diseases with less adverse effect. Plant contains abundant natural compounds such asalkaloids, flavonoids, saponins, steroids, tannins and other nutritional compounds.
These naturalproducts are derived from various parts of plant such as leaves, stems, roots shoots, flowers,barks, and seeds. Recently, many studies have proved that the plant extracts act as a potentialprecursor for the synthesis of nanomaterial in non-hazardous ways. Since the plant extractcontains various secondary metabolites, it acts as reducing and stabilizing agents for thebioreduction reaction to synthesized novel metallic nanoparticles. The non-biological methods(chemical and physical) are used in the synthesis of nanoparticles, which has a serious hazardousand high toxicity for living organisms. In addition, the biological synthesis of metallicnanoparticles is inexpensive, single step and eco-friendly methods. The plants are usedsuccessfully in the synthesis of various greener nanoparticles such as cobalt, copper, silver, gold,palladium, platinum, zinc oxide and magnetite. Also, the plant mediated nanoparticles arepotential remedy for various diseases such as malaria, cancer, HIV, hepatitis and other acutediseases 137.Huimei Chen.
, et al. said that facile and eco-friendly method for the preparation of sub-10nmNinanoparticles (Ni NPs) has been developed based on the bioreduction of aqueous Ni (II)16precursors with alfalfa extract. The XRD and XPS characterization results indicated the facecentered-cubic and zero-valent of Ni NPs, respectively. The size of the crystalline Ni NPs couldbe simply tuned by adjusting the concentration of alfalfa extract and strongly depended on thebioreduction of Ni (II). The bio-molecular analyses of the extract also showed that flavonoidsand reducing sugars play showed important roles in the bioreduction of Ni (II) 138.Umesh Kathad.
, et al. showed that the study was to determine the synthesis of coppernanoparticle by green chemistry and biological synthesis. In both method copper source remainsame i.
e. Copper Sulphate. Synthesis of the copper nanoparticles by green chemistry takesnormal time in synthesis by using reducing agent ascorbic acid and size controlling by CTAB.The synthesis of copper nanoparticles by biological method was done using the plant (Artabotrysodoratissimus). It belongs to Annonaceae family. The local name is “Nag champo”. Sizecomparison of particles synthesized via two different techniques were done by Particle SizeAnalyzer (PSA) which indicate that between both methods synthesis by Green Chemistrymethod gives average size particles of 35nm while in case of Biological, it gives 135nm 139.
T. Shahwan., et al. studied that iron nanoparticles were produced using extracts of green tealeaves (GT-Fe NPs). The materials were characterized using TEM, SEM/EDX, XPS, XRD, andFTIR techniques and were shown to contain mainly iron oxide and iron oxohydroxide. Theobtained nanoparticles were then utilized as a Fenton-like catalyst for decolorization of aqueoussolutions containing methylene blue (MB) and methyl orange (MO) dyes. The relatedexperiments investigated the removal kinetics and the effect of concentration for both MB andMO. The concentrations of dyes in aqueous solution were monitored using ultraviolet–visible(UV–vis) spectroscopy.
The results indicated fast removal of the dyes with the kinetic data ofMB following a second order removal rate, while those of MO were closer to a first orderremoval rate. The loading experiments indicated almost complete removal of both dyes fromwater over a wide range of concentration, 10–200 mg L-1. Compared with iron nanoparticlesproduced by borohydride reduction, GT-Fe nanoparticles demonstrated more effective capabilityas a Fenton-like catalyst, both in terms of kinetics and percentage removal 140