Electrospinning functionalized
nanofibre membrane for antibacterial 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
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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
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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
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Agarwal, S., Greiner, A., & Wendorff, J. H. (2008). Use of electrospinning technique for
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Bhardwaj, N. & Kundu, S. C. (2010). Electrospinning: A fascinating fiber fabrication
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Bjorge, D., Daels, N., Devrieze, S. Dejans, P., Camp, T.V., Audenaer, W,... Van Hulle, S. W.
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