Synthesis and Characterization of Silver nanoparticles using green agents Shekhar Pandharipande 1, Sanjeevani Chavhan 2, Akshata Ramteke 3 Abstract In chemical and material sciences, the synthesis of nanosized particles is considered as a developing field of research. In recent years, due to variety of good and astronomical range of research applications, this emerging field has generated attention of various roles in nanoscience and nanotechnology, categorically in nanomedicine. Silver nanoparticles are nanoparticles of silver of between 1-100 nm in size. Silver nanoparticles are of interest because of their unique properties and applications. In this article synthesis of silver nanaparticles was achieved by chemical method utilizing biogenic materials with water and heating treatment. The techniques used to characterize synthesized silver nanoparticles such as for morphological study of silver nanoparticles analytical technique used SEM and for attestation of silver nanoparticles UV Visible spectrophotometer demonstrated absorbance top for reach of 436 446 nm. Index Terms Green agents, potato extract, rice husk, silver nanoparticles, tulsi extract. 1) INTRODUCTION In chemical and material sciences, the synthesis of nanosized particles is considered as a developing field of research. In recent years, due to variety of good and astronomical range of research applications, this emerging field has generated attention of various scientific researchers. These very small particles have a size characteristically around 100 nm and the application of these nanoparticles specially in the fields of biomedicine and bioscience is increasing day by day. Nanoparticles (NPs) can be synthesized by a number of chemical, physical and biological processes, some of these are rather prevalent and others are novel Silver nanoparticles (AgNPs) having very unique properties that include optical, conducting, catalytic, magnetic, antimicrobial and electrical. Green synthesis is a developing branch involving environmentally benign or biogenic materials like plant extracts or powder, fungi, bacteria etc. that are also utilized in the synthesis of nanoparticles. For synthesis of nanoparticles, green method does not require any toxic chemicals & it bids multifarious benefits like pharmaceutical compatibilities, agricultural & biomedical applications, in cost efficiency and most consequential eco friendliness. Silver nanoparticles are nanoparticles of silver of between 1 nm and 100 nm in size. Silver nanoparticle due to those exceptional properties find role in antimicrobial applications, biosensor materials, composite fibers, cryogenic superconducting materials, cosmetic products, and electronic segments. Living organisms are exposed to bacteria, viruses and fungi. Silver nanoparticles are seen as a leader in the fight against pathogenic microbial activity. Compared to the solid form of silver, the increased surface area of silver nanoparticles is a feature responsible for their behaviour in this regard. This results in better contact with microorganisms, and more effective biocidal activity. As indicated by the research silver nanoparticles might be a viable weapon on battle against infections by inhibiting their replication. Their activity has been confirmed even against the HIV-1 and influenza virus. They destroys different types of fungi such as Aspergillus, Candida and Saccharomyces. They act as an effective and fast-acting agent. 2) LITERATURE REVIEW Zoya Zaheer & Rafiuddin have reported the spectrophotometeric and transmission electron microscopic (TEM) data to the shape-directing role of cetyltrimethylammonium bromide (CTAB) on the green extra-cellular synthesis of bio-conjugated Ag-nanoparticles using Ocimum sanctum leaves extract. TEM images revealed that the nanoparticles are mostly spherical (average particle size ranged from 18 to 35 nm) with some truncated triangular nanoplates, aggregated in a beautiful manner to yield locket-like silver and capped by a thin layer of biomolecules of O. sanctum, whereas nanoparticles are highly poly-dispersed in presence of CTAB. The shape and position of wavelength maxima strongly depends on the reaction time, leaves extract and CTAB. The visual observations also suggest that the prefect transparent silver becomes turbid in presence of CTAB after some time. [1] F. Buazar et.al. Developed the facile green methodology to synthesize highly pure, safe and durable zinc oxide nanoparticles (ZnO Nps) using homemade starch-rich potato extract. The ZnO Nps were synthesised using zinc nitrate and potato 292
Figure 1: The photographs of step wise procedure followed in synthesis on silver nanoparticles 293
Extract, and the whole reaction is carried out for 30 min at 80 0 C. In the synthesis, starch-rich potato extract acted as the reducing agent and as a stabilizing layer on freshly formed ZnO Nps. Hexagonal shaped ZnO Nps with size about 20 to 1.2 nm were synthesised and characterized using X-ray diffraction, transition electron microscope and scanning microscopy analyses. Fourier transform infrared spectral analysis indicated that highly pure ZnO nanopowders were obtained at higher temperatures. The use of environmentally benign and renewable material as the respective reducing and protecting agents, starch-rich potato extract, as well as a gentle solvent medium (H2O), offered a simple and quite efficient procedure for the synthesis of ZnO Nps in neutral medium with promising potential for biological and biomedical applications. [2] Parsa Dar, et.al. Synthesized silver nanoparticles using three different biogenic materials Multani mitti (Fullers earth), Tomato (Solanum lycopersicum) seeds & Rice Husk (Oryza sativa). The possible presence and variability of comprehensive biomolecules in these materials turned as capping and reducing agents which optimize the reduction rate and stabilization of silver nanoparticles. Characterizations were done by using ultraviolet-visible (UV-Vis) spectroscopy, Scanning electron microscope (SEM), Fourier transform infrared spectroscopy (FTIR) and X-ray diffraction (XRD). Stable silver nanoparticles of average size 4.6, 41.1 and 10.6 nm were obtained for Multani mitti, tomato seeds and rice husk respectively. Phenolic and carboxylic biomolecules were identified as active reducing agents of Ag ++ to AgO. The antimicrobial activity was carried out against Klebsiella pneumonia, Salmonella enterica, Escherichia coliand Staphylococcus aureus strains by using well diffusion method. Maximum zone of inhibition (ZOI) was found against Staphylococcus aureus by all of the three biogenic materials. [3] 3) PRESENT WORK Material and Methodology Raw materials and Chemicals: Potato Extract, Rice Husk, Multani Mitti, Tulsi, Silver Nitrate, Distilled Water, Ammonia Solution, Ethanol. Objectives: The main objective of present work is synthesis and characterization of silver nanoparticle using green agents like tulsi extract, multani mitti, tomato seed powder & rice husk powder. Process Description: The procedure for synthesis of silver nanoparticles using biogenic materials with water by heat treatment is as follows:- Run 1 Known amount of rice husk powder, silver nitrate and water is taken. Run 2: known amount of rice husk powder, silver nitrate and tulsi extract is taken. Run 3: known amount of tomato seeds powder, silver nitrate, water and potato extract is taken. Run 4: known amount of multani mitti powder, silver nitrate, water and potato extract is taken. The respective mixtures are heated for 1hr 30 min at 100 0 C with continuous agitation. After getting the black solid particles, the mixture is cooled to room temperature. Known amount of ammonia is added to the cooled mixture run 1 and 2. The samples of these mixtures are analyzed for ascertaining formation of silver nanoparticles using UV Spectroscopy. Some of the samples are further dried & solid samples are analyzed for surface morphology using SEM. The photographs of step wise procedure followed in synthesis on silver nanoparticles are shown in figure 1. 4) RESULT AND DISCUSSION SEM analysis: Figure 2. a to h show typical photographs of the studies of silver nanoparticles by means of SEM. Around the examined area; one can notice the presence of objects of sizes within less than too few µm. It can be observed that spherical shaped Ag particles are adhered onto rice husk surface. UV-spectrophotometer analysis: The ascertainment of formation of silver nanoparticles is done by using UV-Spectroscopy analysis. Figure 3 shows the UV-visible spectra recorded for AgNPs using tulsi extract & rice husk with ammonia, rice husk with ammonia, tomato seeds with potato extract & multani mitti with potato extract respectively. As the biogenic materials were used the mixture underwent a change in colour from yellowish brown to black due to silver ion reduction which showed formation of silver nanoparticles. Absorption spectra of AgNPs formed in the reaction media has absorbance peak at 400 to 500 nm for biogenic materials. The actual peak in figure 3 shows the absorbance more in Run 1 & Run 2 comprising of used of tulsi extract & rice husk with ammonia and rice husk with ammonia respectively. UV-spectrophotometer readings for silver nanoparticles as reported in literature are compared with that of present work samples. Based on the comparison, it can be said that AgNO3 have been formed successfully as the peak around 400 matches with that reported in literature for pure Ag. 294
a: Tulsi extract without ammonia b :Tulsi extract without ammonia c : Rice husk powder with ammonia d : Rice husk powder with ammonia e : Rice husk powder & tulsi extract with ammonia f: Rice husk powder & tulsi extract with ammonia g: Multani mitti wih potato extract h: Multani mitti with potato extract Figure 2: 1a&1b, 2a & 2b, 3a & 3b, 4a & 4b shows silver nanoparticles using biogenic materials 6 5 Absorbance 4 Tulsi extract & Rice husk 3 1.8804 2 1.9237 1.6496 1.3535 1.4539 1 0.7042 0.5385 0.3201 0 0 100 200 300 400-1 Rice husk & Water 0.8642 500 600 700 800 900 1000 Wavelength Figure 3: UV Visible spectroscopy analysis 295
5) CONCLUSION The objective of the present work was to synthesize nanoparticles of silver using green agents. The green agent included extracts of potato pulp & tulsi as reducing agent & multani mitti, rice husk powder, tomato seeds powder as stabilizing agent. The experimental runs have been conducted and the characterization of silver nanoparticles synthesized has been carried out using SEM (Scanning Electronic Microscopy) and UV-Spectroscopy based on observations, result and discussion it can be said that present work has successfully synthesized silver particles in the range of few 100nm. The best particles size is obtained for rice husk with ammonia as green agent. ACKNOWLEDGMENT Authors are thankful to Director of L.I.T. Nagpur for facilities & encouragement provided throughout work. The Authors are thankful to H.O.D. Chemical Engineering department, VNIT, Nagpur for FTIR analysis. REFERENCES [4] M. Puchalski, P. Dabrowski, W. Olejniczak, P. Krukowski, P.Kowalczyk and K. Polanski, "The study of silver nanoparticles by scanning electron microscopy, energy dispersive X-ray analysis and scanning tunnelling microscopy," Materials Science-Poland, vol. 25, no. 2, pp. 473-478, 2007. Shekhar L. Pandharipande is an Associate Professor in Chemical Engineering Department of Laxminarayan Institute of Technology, Rashtrasant Tukadoji Maharaj University, Nagpur. He did his masters in 1985 & joined LIT as a Lecturer. He has coauthored three books titled Process Calculations, Principles of Distillation & Artificial Neural Network. He has two copyrights elite-ann & elite-ga to his credit and two patents are filed as coworker and has more than 60 papers published in journals of repute. Sanjeevani Chavhan is a 8 th semester B. Tech. (Chemical Engineering) student from Laxminarayan Institute of Technology, Nagpur [1] Z. Zaheer and Rafiuddin, "Bio-conjugated silver nanoparticles: From Ocimum sanctum and role of cetyltrimethyl ammonium bromide," Colloids and Surfaces B: Biointerfaces, vol. 108, pp. 90-94, 2013. [2] F. Buazara, M. Bavia, F. Kroushawib, M. Halvania, A. Khaledi-Nasabe and S. Hossieni, "Potato extract as reducing agent and stabiliser in a facile green one-step synthesis of ZnO nanoparticles," Journal of Experimental Nanoscience, 2015. [3] P. Dar, U. Waqas, A. Hina, J. Anwar, A. Dar, Z. Khan and T. Shafqat, "Biogenic Synthesis, Characterization of Silver Nanoparticles Using Multani mitti (Fullers Earth), Tomato (Solanum lycopersicum) seeds, Rice Husk (Oryza sativa) and Evaluation of their Potential Antimicrobial Activity," J.Chem.Soc.Pak, vol. 38, no. 04, pp. 665-675, 2016. Akshata Ramteke is a 4 th semester M.Tech (Chemical Engineering) student from Laxminarayan Institute of Technology, Nagpur 296