Green synthesis of nanoparticles

Green synthesis of nanoparticles

1. Green synthesis of nanoparticles

2. TERMINOLOGIES Nanoparticles Particles having atleast one dimension in the range of 1-100 nm Green Chemistry Utilization of a set of principles that reduces or eliminates the use or generation of hazardous substances in the design, manufacture, and application of chemical products Green Synthesis of Nanoparticles Use of biological routes such as those involving microorganisms, plants etc. for the synthesis of nanoparticles .

3. PRINCIPLES OF GREEN CHEMISTRY Prevent Waste Atom Economy Less Hazardous Chemical Synthesis Designing Safer Chemicals Safer Solvents Design for Energy Efficiency Use of Renewable Feedstock Reduce Derivatives Catalysis Design for Degradation Real Time Analysis for Pollution Prevention Inherently Safer Chemistry for Accident Prevention

4. DIFFERENT APPROACHES TO NANOFABRICATION TOP-DOWN APPROACH Material is fragmented to yield a nanoparticle Long Execution Time BOTTOM-UP APPROACH Assembling individual atoms and molecules to form nanoparticle Short Execution Time

5. SYNTHESIS METHODS PHYSICAL METHOD CHEMICAL METHOD BIOLOGICAL METHOD MECHANICAL METHODS CO-PRECIPITATION METHOD SYNTHESIS USING PLANT EXTRACTS VAPOUR DEPOSITION SOL-GEL METHOD SYNTHESIS USING ENZYMES SPUTTER DEPOSITION MICROEMULSIONS SYNTHESIS USING AGRICULTURAL WASTE ELECTRIC ARC DEPOSITION HYDROTHERMAL SYNTHESIS ION BEAM TECHNIQUE SONOCHEMICAL SYNTHESIS MOLECULAR BEAM EPITAXY MICROWAVE SYNTHESIS

6. GREEN SYNTHESIS OF NANOMATERIALS Physical Method – time and energy consuming, synthesis at high temp. and pressure Chemical Method – simple, inexpensive and low temp. synthesis method, use of toxic reducing and stabilizing agents makes it harmful Green Method – easy, efficient, and eco-friendly. Eliminates the use of toxic chemicals, consume less energy and produce safer products and by products Example – bacteria for Au, Ag, Zn and Fe NPs; yeasts for Ag and Pb NPs; plants for Au, Ag, Pd and Pt NPs

7. BIOLOGICAL METHODS Used for synthesis of highly stable and well-characterized NPs Rapid Synthesis, controlled toxicity and size characteristics, economical and eco-friendly Sizes and morphologies controlled by altering conditions such as pH, substrate concentration, temperature, mixing speed and exposure time. Different Synthesis Methods Use of plant extracts Use of waste Use of enzymes and microorganisms

8. 1. SYNTHESIS USING PLANT EXTRACTS

9. ADVANTAGES Environmental friendly Easily scaled up for large synthesis of nanoparticles No need of high temperature, pressure, energy and toxic chemicals More advantageous over use of micro-organisms by less elaborate process of maintaining cultures Reduces cost of micro-organism isolation and their culture media

10. DISADVANTAGES Plants cannot be manipulated as the choice of nanoparticles through optimized synthesis through genetic engineering Plant produce low yield of secreted proteins which decreases the synthesis rate

11. 2. SYNTHESIS USING WASTE

12. ADVANTAGES Easily available and does not require rigorous processing Directly used for NP synthesis Option for waste management Leads to fast and cost effective approach Does not induce toxic NP

13. 3. SYNTHESIS USING ENZYMES/MICROORGANISMS Microbial synthesis of nanoparticles is a green chemistry approach that interconnects the fields of nanotechnology and microbial biotechnology. A bottom-up approach used. Nanoparticle formation occurs due to the reduction/oxidation of metallic ions. Nanoparticle formation can be either extracellular or intracellular depending on the microorganism. Many bacteria, fungi and plants have the ability to synthesize metallic nanoparticles and all have their own advantages and disadvantages.

14. Example: Synthesis of Silver nanoparticle by bacteria. Ag nanoparticles have been synthesized using Pseudomonas stutzeri AG259 bacterium . Mechanism: NADH NAD+ e- NADH dependent reductase enzyme Ag + Ag nanoparticle

15. Ag nanoparticles prepared were accumulated in periplasmic space of bacteria and were 36-45 nanometer size. This bacteria in conc. a queous solution of silver nitrate produce nanoparticles upto 200 nm in size. Similarly, many other bacterial species are used like Escherichia coli, Klebsiella pneumonia, Lactobacillus spp., Bacillus cereus, Corynebacterium sp., and Pseudomonas sp ., etc. Other microorganisms like actinomycetes , viruses, fungi, algae, yeasts, are also used for nanomaterial synthesis.

16. Advantages: Clean, non-toxic, biocompatible and eco-friendly method for synthesis of nanoparticles. C ost effective, safe and sustainable. Bacteria are easy to handle and can be easily manipulated. Disadvantages: C ulturing of micro-organisms is time-consuming. Difficult to have control over size, shape and crystallinity. Particles are not mono-dispersed and rate of production is slow.

17. CONCLUSION Different methods (physical, chemical and biological) have been developed to obtain NPs of various shapes and sizes. Biological method of NPs is economically and environmentally friendly alternative to chemical and physical approaches. It provide a new possibility of synthesizing NPs using natural reducing and stabilizing agents. It has faster synthesis rates, controlled toxicity and well- characterized NPs. This method is used in various areas such as pharmaceuticals, cosmetics, foods and medical applications.

18. REFERENCES Ahmed, S., Ahmad, M., Swami, B.L., Ikram , S., 2016. A review on plants extract mediated synthesis of silver nanoparticles for antimicrobial applications: A green expertise. J. Adv. Res. 7, 17–28. doi:10.1016/j.jare.2015.02.007 Kalishwaralal , K., Deepak, V., Ram Kumar Pandian , S., Kottaisamy , M., BarathManiKanth , S., Kartikeyan , B., Gurunathan , S., 2010. Biosynthesis of silver and gold nanoparticles using Brevibacterium casei . Colloids Surfaces B Biointerfaces 77, 257–262. doi:10.1016/j.colsurfb.2010.02.007 Makarov , V. V., Love, A.J., Sinitsyna , O. V., Makarova , S.S., Yaminsky , I. V., Taliansky , M.E., Kalinina , N.O., 2014. “Green” nanotechnologies: Synthesis of metal nanoparticles using plants. Acta Naturae 6, 35–44. doi:10.1039/c1gc15386b Shah, M., Fawcett, D., Sharma, S., Tripathy , S.K., Poinern , G.E.J., 2015. Green synthesis of metallic nanoparticles via biological entities, Materials. doi:10.3390/ma8115377 Sharma, D., Kanchi , S., Bisetty , K., 2015. Biogenic synthesis of nanoparticles : A review. Arab. J. Chem. doi:10.1016/j.arabjc.2015.11.002 N.Pantidos and L. E Horsfall, ‘ Biological Synthesis of Metallic Nanoparticles by Bacteria, Fungi and Plants’; Nanomedicine & Nanotechnology ,2014 ( vol 5). Monaliben Shah , Derek Fawcett , Shashi Sharma , Suraj Kumar Tripathy and Gérrard Eddy Jai Poinern : a review on Green Synthesis of Metallic Nanoparticles via Biological Entities,Materials 2015.(7278-7308)