Da. Wang et al., Blends of stearyl poly(ethylene oxide) coupling-polymer in chitosan as coating materials for polyurethane intravascular catheters, J BIOMED MR, 58(4), 2001, pp. 372-383
To optimize the surface biocompatibility of the intravascular catheter, an
amphiphilic coupling-polymer of stearyl poly (ethylene oxide) -co- 4,4 ' -m
ethylene diphenyl diisocyanate-co- stearyl poly (ethylene oxide), for short
MSPEO, was specially designed as the surface modifying additive (SMA), The
blend of MSPEO in chitosan was coated on the outer wall of the catheters b
y the dip-coating method. The surface analysis was carried out by ATR-FTIR
and contact angle measurements. The surface enrichment of MSPEO was confirm
ed. On the water interface, the larger the molecular weight of PEO was, the
higher the surface enrichment, While on air interface, the case was the co
ntrary, Three kinds of static test of clotting time, plasma recalcification
time (PRT), prothrombin time (PT), and thrombin time (TT), as well as the
static platelet adhesion experiment were carried out. The results indicated
that the coated surface could resist the clotting effectively. In order to
test the blood-compatibility of the coated catheters under a shear of bloo
d flow, the dynamic experiment was performed through a closed-loop tubular
system with the shear rate of 1500 s(-1). The results of blood regular test
ing at six different times (0, 5,10, 20, 30, and 60 min) indicated that the
biocompatibility of the coating was nearly ideal. Finally, the SMA-MSPEO w
as proved to be non-chronic-toxic by animal experiments with rats and suita
ble as a coating material for clinical use. (C) 2001 John Wiley & Sons. Inc
.