QUANTITATION OF ADSORPTION AND CONJUGATION OF PLASMA-PROTEINS BY RESIDUAL GLUTARALDEHYDE IN FIXED COLLAGENOUS TISSUE WITH RADIOIODINATED PLASMA-PROTEINS

Residual glutaraldehyde (CA) in collagenous cardiovascular tissue pros theses after multiple saline rinses remains in the prostheses and acco unts for adsorption and conjugation of a variety of plasma proteins. T his may account for later beneficial or adverse effects. Human serum a lbumin (SA), gamma globulin (GG), and fibrinogen (FB) were iodinated w ith I-125 using the iodogen-transfer technique. Bovine pericardium (PC ) was fixed with 0.5% CA for 24 hr and rinsed to remove excess GA. Fre sh and GA-fixed PC (FRPC, CAPC: 1 x 1 cm(2)), in triplicate, were incu bated with 0.5-1.0 mu Ci of tracers in human, porcine, or bovine blood (2 ml) for a period of 0.5, 1, 2, and 3 hr and washed (5x) with salin e. Maximum adsorbed proteins per unit weight of collagen (pmol/mg of P C, mean +/- SD) at 3 hr on FRPC and GAPC were quantified with a gamma counter. Fixed PC absorbed significantly more plasma proteins from blo od than fresh PC. These conjugated plasma proteins are tightly bound t o fixed PC. The adsorbed and conjugated plasma proteins for GAPC and F RPC have the same sequence: SA > CG > FB vs SA > GC > FB. Protein conj ugation may affect the remodeling of collagenous cardiovascular tissue prostheses post implantation.