1. Abstract
AYESHA KHANAM1, ALISON JACOB1 AND HOWARD W.T. MATTHEW1, 2
1 Department of Biomedical Engineering,
2 Department of Chemical Engineering and Materials Science
Dry vs. Hydrated Chitosan Fibers
Materials and Methods - Fibers
Results
Tensile Testing
Material Properties of Chitosan-Based Fibers and Fiber Embedded
Scaffolds
In the United States, nearly 1 in 100 babies are born
with heart defects. Defects such as heart valve
deficiency cannot be treated so easily, causing the
infants to have open heart surgery every year. To settle
this issue, we contributed to a study of chitosan-based
material properties that can be used to engineer tissue
for mechanical heart valves. Chitosan was used
because it is a polyelectrolyte with reactive functional
groups, gel-forming capability, high adsorption capacity
and biodegradability. Chitosan can also go under
several types of modifications. In this study, we used
glycidyl methacrylate (GMA) chitosan fibers with UV
cross-linking. With those fibers, we first tested their
resilience with the tensile testing when the fibers were
dry and hydrated. We then, included the fibers in the
scaffolds and tested the strength of fiber embedded
scaffolds. The objective of the research is to make the
fibers stronger.
Chitosan
GMA chitosan fibers Cross-linked fibers with UV
light
18 Gauge
Chitosan with 4x
Objective
18 Gauge
Chitosan with
20x Objective
30 Gauge 0.25
GMA with 4x
Objective
30 Gauge
Chitosan with 20x
Objective
Dry Chitosan Fibers
Hydrated Chitosan
Fibers
18 G
Chitosan with
4x Objective
18 G chitosan 4x
objective after
equilibration
30 G 0.25 GMA
Chitosan with 4x
Objective
30 G Chitosan
with 4x Objectives
•Cross-linked fiber embedded scaffolds are stronger and
stiffer than scaffolds with no fibers.
•Centrifuge chitosan solutions at the speed of 5000rpm.
for 10-15 minutes.
•The rate was 0.5mL/min.
•During cross-linking with the UV lamp, beaker and the
UV lamp were covered with aluminum foil to keep the
concentration of UV light
Fibers were able to be more stiffer and stronger via
cross-linking and thus, cross-linked fiber embedded
scaffolds were stronger and stiffer as well
Future Work
In the future we will make non-woven scaffolds with chitosan
fibers by felting. Then, we will compare the non-woven scaffolds
and cross-linked chitosan fibers. Lastly, we will test both kinds of
scaffolds with cells to evaluate the cell growth on them.
Materials and Methods - Scaffolds
•Centrifuge chitosan solution at the speed of 5000rmp.
for 10 minutes.
•Fill dishes with 5mL chitosan solution.
•The dishes with fibers (figure 1 ) were frozen in dry ice
and alcohol bath for 3 hours.
•For fiber embedded scaffolds (figure 2), fibers were cut
into 2 mm (length) & were layered between chitosan
solution.
•Afterwards, scaffolds were freeze dried for 24 hours.
Chitosan Scaffolds
figure 1
Fiber Embedded Chitosan Scaffolds
Figure 2
Acknowledgements
•American Chemical Society
•Project SEED (Summer Educational Experience for Disadvantaged
0.00
10,000.00
20,000.00
30,000.00
40,000.00
50,000.00
60,000.00
70,000.00
80,000.00
0 0.1 0.2 0.3 0.4 0.5 0.6
Stress(Pa)
Strain
Scaffolds with: Chitosan Solution, Chitosan Fibers Embedded, 0.25:1
& 1:1 Crosslinked Chitosan Fibers Embedded, & Annealed Chitosan
Fiber Embedded
Chitosan Scaffolds
Chitosan Fiber Embedded
0.25:1 GMA-Chitosan
Cross-linked Fiber
Embedded
Annealed Chitosan Fiber
Embedded
UTS % of Elongation
Chitosan 19,460.00 Pa 0.49%
Chitosan Fiber 19,460.00 Pa 0.20%
0.25:1GMA Crosslinked 48,590.00 Pa 0.30%
1:1 GMA Crosslinked 51,530.00 Pa 0.14%
GMA Crosslinked Annealed
Fiber
69,600.00 Pa 0.13%