Bioactivities of Chitosan and Its Derivatives - Chitosan Based Hydrogels: Functions and Applications - page 132

(a) (b)

10 μm EHT = 1500 W

WD = 26 mm

Signal A = MPSE
Photo no = 1633

Date 27 May 2000
Time 20:33:15

10 μm EHT = 1500 W

WD = 26 mm

Signal A = MPSE
Photo no = 1640

Date 27 May 2000
Time 20:33:02

Mag = 600 X Mag = 180 XX

(c) (d)

10 μm EHT = 1500 W

WD = 23 mm

Signal A = MPSE
Photo no = 1657

Date 27 May 2000
Time 19:57:13

10 μm EHT = 1500 W

WD = 23 mm

Signal A = MPSE
Photo no = 1630

Date 27 May 2000
Time 19:30:00

Mag = 600 X Mag = 150 XX

Figure 3.8
SEM images of the morphology of PRP contacted surfaces: (a) blank PE-1 h (×600), (b) blank PE-1 h (×1500), (c)
OBCS-grafted PE-1 h (×600), and (d) OBCS-grafted PE-1 h (×1500).

Material biocompatibility is generally considered to have a relation with the protein
adsorption process, because adsorbed proteins may trigger the coagulation sequence [119].
In the present work, the PE surface and the OBCS-modified PE surface were studied in
relation to adsorption of BFG in vitro . Table 3.2 shows the adsorption of BFG onto PE sur-
faces from the protein solution (0.1 mg/mL). These results demonstrate that grafting OBCS
onto the PE surface decreases fibrinogen adsorption.
O -Carboxymethylchitosan (OCMCS) is another blood-compatible chitosan derivative. It
was prepared as follows. Chitosan (2 g) was immersed into a 25 mL 50 wt% NaOH solution
to swell and alkalize for 24 h. Alkalized chitosan was crushed into a filtration cake and then
transferred into a flask. Monochloroacetic acid (5 g) was first dissolved in isopropanol (25 mL),
the solution was added dropwise into a flask for 20 min, and the reaction was allowed to

TAble 3.2
BFG Adsorption onto Blank PE and OBCS-Immobilized PE Film

Polymer Film BFG Adsorption (μg/cm 2 )

Blank PE 2.116 ± 0.077

OBCS-immobilized PE 1.315 ± 0.097