國立中興大學 103 學年度第一學期食品暨應用生物科技學系專題討論
Preparation and characterization of genipin cross-linked porous chitosan–
collagen–gelatin scaffolds using chitosan–CO2 solution
Author: Grzegorz Gorczyca, Robert Tylingo, Piotr Szweda, Ewa Augustin, Maria
Sadowska, Sławomir Milewski
Journal: Carbohydrate Polymers
Reporter: 黃翎 7102043004
Date: 2014.11.2
Instructor: Dr. Wen
Host: 王嘉煒
Abstract
1.
Introduction
Nature polymers such as chitosan, collagen and gelatin can be used in the
construction of wound healing devices is attractive, because of their
biocompatibility, possibility of various chemical modifications and low cost of
production. To avoid the inconveniences of residual acid removal from the
material after drying, carbon dioxide saturation aqueous was used for chitosan
blend formulation. With the use of gaseous CO2, chitosan-collagen-gelatin
scaffolds was fabricated. A nature non-cytotoxic compound, genipin, was
chosen as a cross-linking agent to stabilize the structure of the scaffold.
2.
Experimental
i.
Material: chitosan, genipin, lysozyme, ninhydrin solution, DPPH,
ABTS(NH4)2, ferrozine and fish proteins which were extracted from salmon
skin.
ii.
Flow Chart
Preparation of genipin cross-linked chitosan-collagen-gelatin scaffolds
with using chitosan-CO2 solution.
Cross-linking
degree
Morphological
examination
Swelling/
dissolution
tests
Water vapour
transmission
rate (WVTR)
Biodegradation
studies with
lysozyme
Mechanical
properties
Biocompatibility
tests
Antioxidant
activity
3.
i.
ii.
Results and discussion
Morphology of the chitosan-protein scaffolds
As the genipin concentration increased from 0.5% to 2.0%, the pore
cross-sectional area increased by 180 and 1100 μm2 compared with the
non-cross-linked scaffold. And the increased porosity with increased genipin
concentration showed a similar pattern of pore cross-sectional area.
Swelling/dissolution tests
The cross-linked scaffolds had a higher swelling capacity compared with the
corresponding non-cross-linked scaffold because of the weak mechanical
properties of the non-cross-linked scaffold. The swelling capacity of the
chitosan–protein scaffold cross-linked with 0.5% genipin measured in distilled
water is twice than measured in a medium with a salt composition similar to
that of wound exudate.
An increased genipin concentration decreased the scaffold dissolution as
iii.
iv.
v.
4.
the cross-linking degree increased. Because chitosan and collagen are insoluble
in water, the weight loss is related mainly to the dissolution of gelatin.
Texture profile
When the concentration of genipin increased from 0% to 2.0%, the
compressive stress of the dry scaffold increased from 12.11 kPa to 29.17 kPa ,
which indicated that the cross-linking reaction increased the mechanical
strength of the scaffold. But when the scaffolds were swollen, the compressive
stress value was highest for the non-cross-linked sample, and decreased as the
genipin concentration increased. Each cross-linked scaffold retained its 3D
structure after fatigue test but the non-cross-linked one not. This result
indicated that the cross-linked scaffold should maintain appropriate mechanical
properties during application in wound healing.
Antioxidant activity
The chitosan–protein scaffold cross-linked with 0.5% genipin revealed
significantly higher antioxidant activity than the control materials (alginate
hydrocolloid dressing and cotton gauze dressing).
Biocompatibility
The chitosan–protein scaffold cross-linked with 0.5% genipin didn’t induce
cytotoxicity and the fibroblasts grew uniformly in the pores of scaffold structure.
Conclusions
The chitosan–protein scaffold has the basic desirable properties for wound
healing application. The scaffold components had antioxidant properties and
were not cytotoxic; therefore, the chitosan–protein scaffold may accelerate the
healing process.