Electrospinning functionalized nanofibre membrane for anti-bacterial nanofiltration systems

1. Electrospinning functionalized nanofibre membrane for anti-bacterial nanofiltration systems ConorKeevey (AOS) Garrett Nekic (AOS) Darryl Chai (HCI) Sit Han Zhe (HCI)

2. 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.

3. Background • Copper nanoparticleshave shownto possess antimicrobial properties against bacteria such as Escherichia Coli and Bacillus subtilis(Faheem et al, 2011). • Past research has also shown that chlorhexidinedigluconate could kill both gram positive and gram negative bacteria (Chen et al., 2008).

4. 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.

5. Objectives • Confirm the effectiveness of chlorhexidinedigluconate and copper nanoparticleselectrospun for the log removal of bacteria while integrated in separate nanofibre membranes • Determine the effectiveness of a combination of chlorhexidinedigluconate and copper nanoparticleselectrospun into the same membrane for water purification

6. Hypothesis • A combination of copper nanoparticles and chlorhexidinedigluconate is more effective than the individual functionalising agents or no functionalising agents when electrospun into nanofibres.

7. Variables • Controlled Variables: Ambientmeasurements, type and amount of bacteria and water, spinningparameters, size of mesh, methodsused for filtration and measurements • Independent Variable: Type(s) of anti-bacterial agent electrospunwithpolymer • Dependent Variable: The total log removal of colonyformingunits (CFUs)

8. Materials • Aceticacid(18 M glacial) • Formicacid (98% concentration) • Nylon 6 ([-NH(CH2)5CO-], Sigma Aldrich) • Nutrient agar broth • Escherichia coli k-12 (ATTC) • Bacillusmegaterium(ATTC) • Sterilised water • Bleach

9. Apparatus • Electrospinning apparatus • Petridishes • SterileSpreaders • Micropipettes • AA Spectrophotometer • Autoclave • Beakers • Buchner Funnel • Flask

10. Preparation of Copper nanoparticles

11. Preparation of Nanofibres (Daels et al., 2011)

12. TestingwithBacteria

13. TestingwithBacteria http://image.tutorvista.com/content/organic-compounds/filtration-buchner-funnel.jpeg

15. Thank You

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