SYNTHESIS AND CHARACTERIZATION OF SILVER NANOPARTICLES USING LEAF EXTRACT OF “SANSEVIERIA ROXBURGHIANA” AND ITS APPLICATION OF WATER TREATMENT

Synthesis of silver nanoparticles by Bottom up process using natural plant extract is considered to be the most appropriate method on the environmental issues. It is observed that sansevieria roxburghiana (marul) has been used traditionally as herbal medicine for numerous pharmacological applications. Very simple single -step synthesis at ambient temperature through the reduction of aqueous chloroaurate ions (AuCl4 −) with the aqueous extract of the sansevieria roxburghiana leaves. The prepared AuNPs were characterized using field emission scanning electron microscopy (FESEM), UV-vis spectroscopy, FTIR and XRD analysis. That synthesized nanoparticles are introduced in sewage water treatment for its antibacterial action. Introduction Nanoparticles can be easily synthesized using different methods by various approaches available for the synthesis of silver nanoparticles include chemical [1], electrochemical [2], radiation [3], photochemical methods [4] and Langmuir-Blodgett [5] and biological techniques [6]. But most of the chemical methods used for the synthesis of nanoparticles involve the use of toxic, hazardous chemicals that create biological risks and sometime these chemical processes are not ecofriendly. This enhances the mounting need to develop environmentally eco-friendly processes through green synthesis and other biological approaches. Sometimes the synthesis of nanoparticles using various plants materials and their extracts can be beneficial over other biological synthesis processes which involve the very complex procedures of maintaining microbial cultures [7]. It is one of the best platforms for synthesis of nanoparticles as it is free from toxic chemicals as well as providing natural capping agents for the stabilization of silver nanoparticles. Now, plant mediated synthesis of metal nanoparticles is receiving lots of attention due to its simplicity, prompt synthesis of nanoparticles of attractive and diverse morphologies and elimination of detailed maintenance of cell cultures and eco-friendliness. Metallic nanoparticles are budding as new carriers which provide way to site-specific targeting and drug delivery by these nanoparticles. Silver (Ag) a noble metal, has potential applications in medicine due to its unique properties such as good conductivity, chemically stable, catalytic activity, surface enhanced Raman scattering and antimicrobial activity, Increases the oral bio-availability and to overcome the poorly water soluble herbal medicines[9-11]. Silver nanoparticles have antibacterial properties mediated by silver ions [12], it used as preservative in food and various food related products [13-14]. There are various methods for silver nanoparticles preparation, for example; sol-gel process, chemical precipitation, reverse micelle method, hydrothermal method, microwave, chemical vapour deposition and biological methods, etc.[15] However; biological methods are preferred for being eco-friendly, cost effective, and not involve the use of toxic chemicals. Green synthesis of nanoparticles is an emerging branch of nanotechnology. Biosynthesis of nanoparticles using plant extracts is the favourite method of green, exploited to a vast extent because the plants are widely distributed, easily available, advancement over physical and chemical methods, safe to handle and with a range of metabolites and compatibility for pharmaceutical and biomedical applications as they do not use toxic chemicals in the synthesis protocols [16-20]. [ VOLUME 5 I ISSUE 4 I OCT.– DEC. 2018] E ISSN 2348 –1269, PRINT ISSN 2349-5138 196u IJRARInternational Journal of Research and Analytical Reviews Research Paper The plants used for AgNps synthesis range from algae to angiosperms; however, limited reports are available for lower plants and the most suitable choice are the angiosperm plants. Parts like leaf, bark, root, and stem have been used for the AgNP synthesis. The medicinally important plants likeBoerhaavia diffusa [23], Tinospora cordifolia [24], Aloe vera [25], Terminalia chebula [26] Catharanthus roseus[27], Ocimum tenuiflorum [28] . Due to its antimicrobial properties, silver has also incorporated in filters to purify drinking water and clean swimming pool water. To generate nanosilver, metallic silver has been engineered into ultrafine particles by several methods; include spark discharging, electrochemical reduction, solution irradiation and cryochemical synthesis. [32] Nano-silver particles are mostly smaller than 100 nm and consist of about 20-15,000 silver atoms. In addition, nanostructures can be produced as tubes, wires, multifactes or films. At the nano-scale, the silver particles exhibit deviating physico-chemical properties (like pH dependent partitioning to solid and dissolved particulate matters) and biological activities compared with the regular metal. Nanosilver particles in medical application, synthesis performance, and toxicity. Finally, possible toxicology was discussed. [39] Green synthesis provides advancement over chemical and physical method as it is cost effective, environment friendly, easily scaled up for large scale synthesis and in this method there is no need to use high pressure, energy, temperature and toxic chemicals. EXPERIMENTAL SECTION Materials The required chemicals were purchased from the following sources: Silver Nitrate (AgNO3) from SigmaAldrich with 99% assay and commercially available marul leaf were collected from M.R.Government Arts College , Mannargudi. De-ionized water (DM) was used for all the experiments. SYNTHESIS TECHNIQUES Preparation of Plant extracts from “Sansevieria Roxburghiana” (Marul) leaves Fresh leaves of “Sansevieria Roxburghiana” (Marul) were collected and washed several times with water to remove the dust particles and then washed with DM water twice. The 100g of plant leafs are cut in to small pieces. Finely cut leaves were placed in a 500 ml Erlenmeyer flask containing 200 ml of DeIonized Water. After that the mixture was boiled for 10 min and filtered using normal filter paper and with cotton to remove centrifuged particle, followed by watt men filter paper of size -40mm. The extract was stored in Room Temperature. Picture of “Sansevieria Roxburghiana”(Marul) leaves Preparation of Silver Nitrate solutions A 0.1689g of 1mM stock solution of AgNO3 in De-Ionized water is prepared. Weighed amount of AgNO3 was carefully transferred in a 1000-ml volumetric flask and de-ionized water was added drop-wise while swirling to dissolve the salt up to the mark. The solution was diluted as required and all the solutions were kept away from light (the containers were wrapped with brown papers) and kept in dark. SYNTHESIS OF SILVER NANOPARTICLES Silver nanoparticles were prepared from aqueous AgNO3 solution (1mM) as a precursor and using the as prepared leaf extract as a reducing agent in aqueous medium. A constant ambient temperature of 250C was maintained throughout the process. Before addition of leaf extract to the AgNO3 solution, the volume of 1mM AgNO3 solution was required to attain a specific concentration (0.05mM, 0.1mM, 0.15mM and 0.2mM, 0.25mm, 0.3mM) of the solution was calculated. [VOLUME 5 I ISSUE 4 I OCT. – DEC. 2018] e ISSN 2348 –1269, Print ISSN 2349-5138 http://ijrar.com/ Cosmos Impact Factor 4.236 Research Paper IJRARInternational Journal of Research and Analytical Reviews 197u A set of six tubes were taken and labeled. The six test tubes were added with various concentrations of AgNO3 solution (0.05mM, 0.1mM, 0.15mM and 0.2mM, 0.25mm, 0.3mM) and leaf extract was added slowly one after another. Finally required volumes of de-ionized water was added (as shown in the Table 2) and stirred continuously and kept in dark atmosphere. The color of the solution changed gradually to brown following the intensity of color becomes increases, depending on the precursor concentration respectively indicating the formation of silver nanoparticles. Plant extract AgNO3 Solution Nanoparticle solution (Plant extract +AgNO3) Formation of silver nanoparticles using plant extract in different concentration. CHARACTERIZATION OF SILVER NANOPARTICLES: Several techniques are used for characterizing different Nanoparticles. Here we have discussed the basic principles of few techniques that have been used for the characterized the silver nanoparticles in this project work. They are absorption (UV-Vis) particle size analyzer, X-ray diffraction (XRD) and Scanning Electron Microscope (SEM) and Transmission Electron Microscope (TEM).