Ch. Bamford et Kg. Allamee, STUDIES IN POLYMER SURFACE MODIFICATION AND GRAFTING FOR BIOMEDICAL USES .2. APPLICATION TO ARTERIAL BLOOD FILTERS AND OXYGENATORS, Polymer, 37(22), 1996, pp. 4885-4889
The technique for polymer surface modification described in earlier pa
pers has been applied to two components of an extracorporeal blood cir
culatory system used in open-heart surgery, with the object of improvi
ng their haemocompatibility. The devices were the arterial blood filte
r composed of nylon membranes and the blood oxygenator consisting of p
olypropylene microporous hollow fibres. Polyacrylamide and, in some ca
ses, a mixture of polyacrylamide and poly(3-aminopropyl methacrylamide
) have been covalently attached to the blood-contacting surfaces. The
basic groups of the latter polymers provided a means of coupling hepar
in to the surface. The extent of heparin coupling was determined by ra
dioactivity measurements with the aid of S-35-labelled heparin. The fo
llowing determinations were made to assess haemocompatibilities: blood
plasma clotting times (PTT); platelet adhesion to the nylon filters;
concentrations of lymphocytes and neutrophils in whole blood after exp
osure to the surfaces. It is concluded that the overall process, which
has the merits of cheapness and simplicity in application, has a bene
ficial effect on haemocompatibility. Copyright (C) 1996 Elsevier Scien
ce Ltd.