PRESENTAT.noman Khan MPhil chemistry research pptx

Education research

1. Supervised by: DR . MUHAMMAD Hafeez Presented by: MARYUM ZEB

2. POPULUS CILIATA (Wall. Ex Royle) MEDIATED SYNTHESIS OF SILVER NANOPARTICLES AND THEIR POTENTIAL BIOLOGICAL APPLICATIONS

3. PRESENTATION OVERVIEW INTRODUCTION MATERIALS AND METHODS CHARACTERIZATION RESULTS AND DISCUSSION CONCLUSION ACKNOWLEDGEMENT

4. INTRODUCTION

5. WHAT ARE NANOPARTICLES? “ Nano ” derived from Greek word “ nanos ”, meaning tiny, very small or dwarf They have high surface area to volume ratio High catalytic activity Enhanced chemical and physical properties The technology that deals with study of nanoparticles is known as nanotechnology Nanoparticles refer to the particles whose size ranges from 1 to 100 nm

6. S ynthesis of Nanoparticles Three general methods for the synthesis of nanoparticles; Physical methods Chemical methods Biological methods Sol-Gel Method, Spinning, Chemical Vapour Deposition, Pyrolysis Mechanical milling, Nanolithography, Laser Ablation Sputtering, Thermal Decomposition F ungi , B acteria , P lants

7. SILVER NANOPARTICLES

8. APPLICATIONS OF AGNPS BIOMEDICAL Cancer therapy Diagnosis Drug delivery Cell imaging FOOD AGRICULTURE Food packaging Interactive food Food quality analysis sensors HEALTH CARE UV protection Topical ointments and creams N utraceutical ENVIRONMENTAL Water disinfection Activated-carbon filters Wastewater treatment TEXTILES UV blocking textiles Anti-stain textiles Medical textiles CATALYSIS Fuel cell catalyst Fuel additive catalysts Hydrogen production catalyst

9. INTRODUCTION TO PLANT USED Scientific name : Populus ciliata Local name : safeda Family : Silicaceae Prefers moist and cool places It also contains active biomolecules that can act as reducing and capping agent POPULUS CILIATA (salicaceae)

10. IMPORTANCE of POPULUS CILIATA ( salicaceae) Populus ciliata is cut and stockpiled to be fed to livestock in the times of food scarcity. It is also used as a fuel. Wooden part is utilized for making packing boxes. Its bark is useful to make stimulants, tonics and blood cleaner. The bark’s paste on mixing with the ash of cow dung can be employed to cure muscular swellings . Populus ciliata can also used for writing, printing and wrapping. Salicin is produced in willow bark and act as an anti-inflammatory agent in the body.

11. AIMS AND OBJECTIVES To synthesize silver nanoparticles by using leaf extract of Populus ciliata . Characterization of Ag NPs by using IR, UV-visible, XRD , TEM, SEM and EDX techniques To adopt the eco-friendly, less toxic and inexpensive method. To observe the biological activity of the nanoparticles.

12. Silver N anoparticles + Leaves Extract AgNO 3 Solution Antibacterial activity TEM images revealed the spherical AgNPs

13. PREPARATION OF LEAF EXTRACT Collection of fresh and healthy leaves LEAVES CHOPPING DRYING OF LEAVES WASHING OF LEAVES 30 g LEAVES+ H2O HEAT (70 ᵒC) FOR 6 h EXTRACT FILTERING AND COOLING

14. PREPARATION OF SILVER NITRATE SOLUTION 0.01 M aqueous solution of AgNO3 was prepared by dissolving 0.169 g of AgNO3 in 100 mL distilled water. AgNO3 solution was kept in dark SYNTHESIS OF AGNPS 20 mL of the extract was added to 50 mL of aqueous silver nitrate (AgNO3) solution (0.01 M). The mixture was stirred and heated at 80 ℃ Colour altered from transparent yellow to reddish brown within 20 min which indicated the synthesis of AgNPs. The synthesized nanoparticles were separated by repeated centrifugation at 5000 rpm for 30 min After centrifugation, AgNPs were washed two times with distilled water. The synthesized NPs were dried in an oven at 100 ℃ and stored in an air tight container for the characterization and antibacterial activities.

15. The inhibitory effect of synthesized AgNPs was verified against both Gram-positive and Gram-negative bacteria Agar well diffusion method was used Gram positive; Streptococcus pyogenes & Staphylococcus epidermidis Gram negative; Klebsiella pneumonia, Pseudomonas pseudoalcaligenes & Serratia marcescom

16. PROCEDURE OF ANTIBACTERIAL ACTIVITY

17. PROCEDURE PREPARATION OF AGAR PLATES SPREADING OF BACTERIAL CULTURE IN AGAR PLATES FILLING OF WELLS WITH PREPARED TEST SAMPLE INCUBATION (37 ℃ ) BORING OF WELLS MEASUREMENT OF ZOI AFTER 24 HRS.

18. CHARACTERIZATION TECHNIQUES . Used for identification of functional groups To study the optical properties To study the crystalline nature and geometry Ag NPs T o study M orphology and particle size of synthesized Ag NPs To study the purity and percentage composition of Ag NPs To study the Internal morphology and size of the s ynthesized nanoparticles EDX UV-VIS SEM XRD IR TEM

19. RESULTS AND DISCUSSION

20. RESULTS Colour Change and UV-Visible Characterization Fourier-transform Infrared Analysis X-ray Diffraction (XRD) Analysis Scanning Electron Microscopy (SEM ) Transmission Electron Microscopy (TEM ) Energy Dispersive X-ray Analysis

21. COLOUR CHANGE The color arouse because of the excitation of surface Plasmon vibrations in the metal NPs The alteration of colour of aqueous Populus ciliata leaf extract from yellow to reddish brown indicates the conversion of silver ions to AgNPs

22. UV-VISIBLE SPECTROSCOPY T he synthesized NPs showed absorbance maxima at 445 nm which is an obvious indication of the fact t hat the synthesized NPs are photosensitive in UV-visible region.

23. UV-VISIBLE SPECTRUM OF SYNTHESIZED AGNPS

24. FOURIER-TRANSFORM INFRARED ANALYSIS Major peaks were detected at 3446 cm -1 , 2999 cm -1 , 1719 cm -1 , 1388 cm -1 , 1212 cm -1 and 503 cm -1 Peak positioned at 1388 cm -1 specified the NO 3 -1 group presence in the residual solution. The peak at 3446 cm -1 indicated OH functional group of hydrogen bonded alcohols or phenols . The absorption peak at 2999 cm -1 represented -CH stretching vibrations of both -CH 2 and -CH 3 functional groups.

25. The peak at 1212 cm -1 represented the C-O group the peak at 1719 cm -1 can be consigned to C=O group of tertiary amides. In extract spectrum this peak was observed at 1652 cm -1 and in AgNPs spectrum it got shifted to 1719 cm -1 . The peak at 503 cm -1 can be attributed to silver oxide (Ag-O). The involvement of compounds from Populus ciliata leaf extract in green synthesis of NPs was established through the shifting of peaks Compounds from Populus ciliata leaf extract which include OH and CO groups have played a significant role in reducing and stabilization of AgNPs

26. X-ray Diffraction (XRD) Analysis The XRD pattern of greenly synthesized Ag-NPs shows four sharp peaks at 2 theta values 38.23°, 44.44°, 64.44° and 77.32° which were due to crystal planes (111), (200), (220) and (311) of crystal system These crystal planes are features of the face center cubic (FCC) silver nanoparticles From the intense diffraction peaks of XRD pattern it is obvious that AgNPs formed using Populus ciliata leaf extract were highly crystalline in nature containing single phase. All the peaks are in well match with the simulated pattern (PDF # 28-6571) of Ag nanoparticles, hence a very pure single phase particles were formed

27. XRD spectrum A substantial peak broadening further indicates the sub-nanometric dimensions of synthesized particles

28. Scanning Electron Microscopy It is apparent from the figure that the nanoparticles were of spherical morphology which got agglomeration in few regions Overall , the synthesized particles are well dispersed and are of smaller size Few voids can also be seen in the SEM micrograph

29. SEM micrograph of the greenly synthesized AgNPs

30. TRANSMISSION ELECTRON MICROSCOPY TEM analysis showed that particles were: spherical in shape with non-uniform size distribution which is also indicated by particle distribution histogram The average size was being estimated using smaller particles which constitute major proportion and , it comes out to be about 4 nm It has been assumed that these smaller particles are the primary and major product Few , relatively larger particles also developed due to the aggregation of these smaller particles

31. TEM micrograph of synthesized AgNPs Size histogram

32. Energy Dispersive X-ray Analysis H igher counts were seen at 3 keV which was attributed to the presence of metallic silver nanoparticles ( AgNPs) The elemental analysis of the synthesized AgNPs exposed the highest proportion of silver (Ag) followed by oxygen ( O) The oxygen peak is from the biological molecules bound to the surface of the synthesized Ag nanoparticles Aluminum (Al) and silicon (Si) peaks in EDX spectrum are because of the sample grid holder which is composed of the Al alloy Magnesium (Mg) peak in the spectrum may be the result of presence of Mg in the chlorophyll of plant extract

33. EDX SPECTRUM OF SYNTHESIZED AGNPS

34. RESULTS OF ANTIBACTERIAL ACTIVITY

35. The strongest antibacterial activity was shown by Gram-negative bacteria (Serratia marcescom ) Inhibition zone of 26 mm was observed for it at the highest concentration used i.e., 25 mg/mL

36. L east activity was shown against Klebsiella pneumonia Klebsiella pneumonia

37. ANTIMICROBIAL ACTIVITY Pseudomonas pseudoalcaligenes Streptococcus pyogenes Staphylococcus epidermidis

38. Antibacterial activities of AgNPs against gram-positive and gram-negative microbes     Bacterial Stains       Organisms Zones of inhibition (mm)     Standard deviation Mean antibacterial activity with 95 % Confidence Interval Pearson correlation between dose and antibacterial activity P = 0.05     Clindamycin phosphate     E1     E2     E3     E4     E5 Gram-negative bacteria Klebsiella pneumonia 22 - 13 14 16 20 7.536 12.6±9.355 0.036 Significant Serratia marcescom 30 13 15 25 25 26 6.261 20.8±7.73 0.032 Significant Pseudomonas pseudoalcaligenes 23 13 15 20 20 22 3.808 18.0±4.728 0.011 Significant Gram-positive bacteria Staphylococcus epidermidis 22 12 15 20 20 22 4.147 17.8±5.148 0.012 Significant Streptococcus pyogenes 30 13 16 20 22 25 4.764 19.2±5.216 N/A

39. CONCLUSIONS The facile Populus ciliata mediated synthesis of silver nanoparticles (AgNPs) was reported for the first time in this study Characterization techniques such as FTIR, XRD, SEM, TEM, UV-Vis spectroscopy and EDX confirmed the synthesis of silver nanoparticles The FTIR analysis depicted the role of functional groups present in leaf extract of Populus ciliata in stabilizing and capping the synthesized nanoparticles XRD data exposed the crystalline nature and face centred cubic (FCC) geometry of the synthesized silver nanoparticles. SEM and TEM disclosed the spherical shape of the synthesized silver nanoparticles. The average size of the silver NPs, calculated via TEM, was 4 nm. Antibacterial activity of the synthesized NPs was also checked which depicted their inhibitory effect against both Gram-positive and Gram-negative bacterial strains We can conclude that this Populus ciliata mediated green synthesis is a better alternative to the conventional physical and chemical approaches used for the synthesis of silver nanoparticles. It possesses a great potential to be used in biomedical applications and most importantly, this reaction was convenient and simple to handle

40. Acknowledgement Thanks to Almighty Allah for giving me strength to complete my research work Dr. M. Hafeez, my Supervisor for his guidance and assistance Dr. Abdur Rehman khan Chairman, Department of Chemistry, for his tremendous facilitation Teaching faculty, friends and Office/labs staff of the Chemistry Department