Download Performance of anti-biofouling coatings under variable and dynamic

Performance of anti-biofouling coatings under variable and dynamic process conditions
Faculty Mentor: Leslie M. Shor, PhD
Asst. Prof, Chem & Biomolecular Engineering
University of Connecticut Storrs CT
Industrial Mentor: Yoram Barak, PhD
Group Leader - Fine Chemicals & Biocatalysis
Research, BASF Inc., Tarrytown NY
Overview. Microbial growth on implanted medical devices is a major cause of implant failure. Bacteria will often
grow on solid surfaces encased in a hydrated polymer matrix called a biofilm. Bacteria in a biofilm require
antimicrobials to be applied at 10, 100, or 1000 times the concentration required in liquid suspension to achieve
similar results, if eradication can be achieved at all. Well-established biofilms on implants require surgical
removal, and biofilm infections of the heart and lungs are often fatal.
Anti-biofilm or anti-biofouling products are big business. However, because biofilms are so difficult to eradicate,
much industrial anti-biofouling research is focused on how to prevent the formation of a biofilm in the first place.
BASF produces many surface coatings and anti-biofouling compounds. However, usually coatings or compounds
are tested under very simplified process conditions, such as a flat, smooth coupon tested under stirred batch or
constant-velocity flow cell conditions.
BASF and the Shor research lab are initiating a new collaboration to develop test systems to study anti-boufouling
products under more realistic geometries and process conditions. Technology already under development in the
Shor lab includes flow cells that permit dynamic operation and real-time observation of bacterial attachment,
biofilm development, or time-dependent eradication of a biofilm. New work will also add the capability to study
effectiveness of coatings or agents on biofouling of surfaces with complex geometries, or under dynamic or
variable flow conditions.
Undergraduate Participant Responsibilities & Benefits. The REU student will work alongside Dr. Shor and
PhD students in the Shor lab. The student will design and construct microfluidic flow cells for real-time
observation of bacterial attachment and biofouling. He or she will learn computer aided design, elements of
photolithography and soft lithography for making microfluidic devices, and computer multiphysics simulation
with COMSOL. The student will also learn to work with microbial cultures, and collect information with
quantitative light microscopy. Meanwhile, experts in the BASF white biotechnology and microbiology research
center in Tarrytown NY will collaborate and provide materials to be used in anti-boufouling testing.
Figure 1. Photolithography techniques are used to create
microfluidic flow cells where biofouling can be studied for
complex geometries and with complex and dynamic
process conditions. A. A silicon wafer with a 40 µm-thick
layer of photo-crosslinked epoxy with 10- to 100- µm
features. From this mold, multiple exact replicas can be cast
and used for study. B and C. Because the geometry is
fixed, flow conditions can be simulated in detail, and
compared exactly with experiments performed under the
exact same geometry. D. Here we show fluorescenceexpressing bacteria forming biofilm-like colonies in a microstructured flow cell under complex flow conditions.
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D
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