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Materials-Metals 2017
Notes:
Page 39
November 16-17, 2017 Paris, France
13th Annual Conference on
Materials Science, Metal and Manufacturing
Journal of Materials Science and Nanotechnology
Volume 1 Issue 2
Characterize the mechanical microenvironment
of a 3-D hybrid biomatrix by laser trap
Ian C Hsu
National Tsing-Hua University, Taiwan
Hydrogel physical properties were tuned by modulating
the type of gelatin and the PEGdA to gel-PEG-Cys
concentrations. Bulk viscoelastic properties were highly
dependent on PEGdA concentration and total water content;
while gel-PEG-Cys concentration was more important
to the swelling profiles. Soft materials including the sIPN
are viscoelastic in nature. The viscoelastic properties of
the material (i.e., the microenvironment) is crucial for
understanding the biomaterial-cell interactions at the cellular
scale, which may provide insight into the behavior of cells
that are entrapped in a 3-D matrix (i.e., sIPN). In this study,
we measured the microrheology of a 3-D matrix by laser trap
system. We entrapped commercially available polystyrene
beads (size: ~1 µ m) in the Gel-PEG-Cys and PEGdA 3400.
While trapped by laser trap, the bead position was recorded
by a QPD sensor, which has resolution down to nano-meter.
The position data was analyzed in frequency domain. The
local viscosity was deduced from the corner frequency of
the position spectrum. For sample 1 and sample 2 we did see
the locational dependent viscosity, especially in the case of
sample 2. In sample 3 and sample 4, the viscosity is too high
to allow the bead performing measurable Brownian motion.
Biography
Ian C. Hsu received his PhD from the University of Wisconsin-Madison, USA,
1989. He then joined Stanford Linear Accelerator Center, Stanford University
as research scientist. He then joined National Tsing Hua University in Taiwan
as associated professor in the Department of Biomedical Engineering at 1991,
and became full professor and chairman of the department in 1998. He has
been a visiting professor of Department of Genetics, Stanford University in 1999
and a visiting professor of Department of Biochemistry, Stanford University in
2007. Dr. Hsu’s research was in the beam physics and later in single molecule
research as well as in biochip development and its biomedical applications. He
has published numerous papers and holds several patents.
Ian C Hsu, Mater Sci Nanotechnol 2017, 1:2