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Electrospinning functionalized nanofibre membrane for anti-bacterial nanofiltration systems. Conor Keevey (AOS) Garrett Nekic (AOS) Darryl Chai (HCI) Sit Han Zhe (HCI). Background. - PowerPoint PPT Presentation
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Electrospinning functionalized nanofibre membrane for anti-bacterial nanofiltration systems
Conor Keevey (AOS)Garrett Nekic (AOS)Darryl Chai (HCI)Sit Han Zhe (HCI)
Background• Electrospinning is a simple and
versatile process that is used to create nanofibre membranes for a variety of applications.
• Scientists have implemented various chemicals into the polymer solution to create modified mesh.
Background• Copper nanoparticles have shown to
possess antimicrobial properties against bacteria such as Escherichia Coli and Bacillus subtilis (Faheem et al, 2011).
• Past research has also shown that chlorhexidine digluconate could kill both gram positive and gram negative bacteria (Chen et al., 2008).
Rationale Lack of access to drinking water
Current conventional methods have their disadvantages:
• Non-controllable pore size• Lack of ability to control nanofiber
composition/ functionalising agents for desired functions
Great demand for a more efficient and cheaper method of water purification.
Objectives Confirm the effectiveness of
chlorhexidine digluconate and copper nanoparticles electrospun for the log removal of bacteria while integrated in separate nanofibre membranes
Determine the effectiveness of a combination of chlorhexidine digluconate and copper nanoparticles electrospun into the same membrane for water purification
Hypothesis A combination of copper nanoparticles
and chlorhexidine digluconate is more effective than the individual functionalising agents or no functionalising agents when electrospun into nanofibres.
Variables Controlled Variables:Ambient measurements, type and amount of
bacteria and water, spinning parameters, size of mesh, methods used for filtration and measurements
Independent Variable:Type(s) of anti-bacterial agent electrospun with
polymer
Dependent Variable: The total log removal of colony forming units
(CFUs)
Materials Acetic acid (18 M glacial) Formic acid (98% concentration) Nylon 6 ([-NH(CH2)5CO-], Sigma Aldrich) Nutrient agar broth Escherichia coli k-12 (ATTC) Bacillus megaterium (ATTC) Sterilised water Bleach
Apparatus Electrospinning apparatus Petri dishes Sterile Spreaders Micropipettes AA Spectrophotometer Autoclave Beakers Buchner Funnel Flask
Preparation of Copper nanoparticles
•Mix copper(II) sulfate with ethylene glycol
•Centrifuge mixture to obtain copper nanoparticles
•Rinse with distilled water and pat dry with filter paper
Preparation of Nanofibres
•Dissolve nylon 6 in acetic and formic acid
•Mix in antibacterial agent (copper nanoparticles/chlorhexidine digluconate)
•Spin an anti-bacterial mesh
(Daels et al., 2011)
Testing with Bacteria
•Grow the Escherichia coli, and Bacillus megaterium using nutrient broth in separate test tubes
•Measure and adjust optical density
•Mix bacteria with sterilised water
•Deposit 100 µL diluted culture into the agar plates (10 plates)
Testing with Bacteria
•Place mesh on circular plate and fasten to cylinder. Place in funnel
• Pour the 500 mL of water through it
•Deposit 100 µL of diluted culture onto the agar plates (10 plates)
•Place the plates in the incubator
http://image.tutorvista.com/content/organic-compounds/filtration-buchner-funnel.jpeg
Thank You
Bibliography• Agarwal, S., Greiner, A., & Wendorff, J. H. (2008). Use of electrospinning technique for
biomedical applications. Polymer, 49, 5603-5621. doi: 10.1016/j.polymer.2008.09.014• Bhardwaj, N. & Kundu, S. C. (2010). Electrospinning: A fascinating fiber fabrication
technique. Biotechnology Advances, 28, 325-347. doi: 10.1016/j.biotechadv.2010.01.004• Bjorge, D., Daels, N., Devrieze, S. Dejans, P., Camp, T.V., Audenaer, W,... Van Hulle, S. W.
H. (2009). Performance assessment of electrospun nanofibers for filter applications. Desalination, 249, 42-948. doi: 10.1016/.j.desal.2009.06.064
• Chen, L., Bromberg, L., Hatton, T. A., & Rutledge, G. C. (2008). Electrospun cellulose acetate. Fibers containing chlorhexidine as a bacteriacide. Polymer, 49, 1266-1275. doi: 10.1016/j.polymer.2008.01.003
• Daels, N., De Vrieze, S., Sampers, I., Decostere, B., Westbroek, P., Dumoulin, A.,...Van Hulle, S. W. H. (2011). Potential of a functionalised nanofibre microfiltration membrane as an antibacterial water filter. Desalination, 275, 285-290. doi: 10.1016/j.desal.2011.03.012
• Faheem, A.S. , Muzafar, A.K. , Saurabah, S, Chung, W.J. & Kim, H (2011). Polyurethane nanofibers containing copper nanoparticles as future materials. Applied Surface Science, 257, 3020-3026
Bibliography• Frey, M. W., & Li, L. (2007). Electrospinning and porosity measurements of
nylon-6/poly(ethylene oxide) blended nonwovens. Journal of Engineered Fibers and Fabrics, 2, 31-37.
• Hem, R.P. , Dipendra, R.P. , Ki, T.N. , Baek, W.I. , Seong, T.H. & Kim, H.Y. (2011). Photocatalytic and antibacterial properties of a TiO2/nylon-6 electrospun nanocomposite mat containing silver nanoparticles. Journal of Hazardous Materials, 189, 456-471
• Lok, C.N. et al. (2006). Proteomic analysis of the mode of antibacterial action of silver nanoparticles. J Proteomic Research, 5(4): 916-24.
• Rutledge, G. C. & Fridrikh, S. V. (2007). Formation of fibers by electrospinning. Advanced Drug Delivery Review, 59, 1384-1391. doi: 10.1016/j.addr.2007.04.020
• Sondi, I., Salopek-Sondi, B. (2004). Silver nanoparticles as antimicrobial agent: a case study on E. coli as a model for Gram-negative bacteria. Journal of Colloid and Interface Science, 275, 177-182
• Y. Dzenis, Science 304 (2004) 1917.• Zussman, E., Theron, A. & Yarin, A. L. (2003). Formation of nanofiber crossbars in
electrospinning. Appl Phys Let, 82, 973-5.
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