Albumin adsorption and retention on C18-alkyl-derivatized polyurethane vascular grafts.
The short-term albumin affinity and thrombo-resistance of a polyether polyurethane vascular graft have been improved. The method is based on the C18 alkylation of the polymer. Thrombus formation by a planimetric technique and albumin retention on wire-reinforced polyurethane tubes, both C18 alkylated and untreated, were measured in short-term (4-h) exposure at femoral arterial sites in the dog. 125I-Albumin was preabsorbed on tubes and then exposed to blood for successive 2-h periods. Albumin uptake on alkylated tubes prior to blood exposure and retention following 2 h of blood exposure were significantly greater than on controls. Following a fast desorption phase in blood, the remaining albumin was more slowly desorbed from alkylated than from control tubes. Reincubation with albumin and blood reexposure produced a similar tendency, suggesting blood conditioning does not reduce the albumin affinity-enhancing property of C18 alkylation in the short term. Blood-preconditioning experiments suggested endogenous albumin has a high affinity for the C18-alkylated surface. Scanning electron microscopic examination showed thrombus and platelet densities were higher on control than on alkylated surfaces. These results suggest in vivo albumin affinity is increased for C18-alkylated polyurethane, which may be linked to decreased thrombus formation on these surfaces.
Eberhart
R C
RC
Department of Surgery, University of Texas Health Science Center at Dallas 75235-9031.
Munro
M S
MS
Williams
G B
GB
Kulkarni
P V
PV
Shannon
W A
WA
Brink
B E
BE
Fry
W J
WJ
D000327:Adsorption; D000818:Animals; D001672:Biocompatible Materials; D001807:Blood Vessel Prosthesis; D004285:Dogs; D005263:Femoral Artery / Q000601:surgery; D011140:Polyurethanes; D012709:Serum Albumin / Q000493:pharmacokinetics*; D013927:Thrombosis / Q000517:prevention & control
D001672:Biocompatible Materials; D011140:Polyurethanes; D012709:Serum Albumin; C115016:polyetherurethane