Adsorption of Human Fibrinogen and Albumin on Polymethylmethacrylate (PMMA), Collagen and Elastin

PMMA-slides were partially coated with a mixture of soluble and fibrillar collagen with Solubilized elastin. The slides were exposed for 2 min at 37°C under laminar flow ¹²⁵I-fibrinogen or ¹³¹I-albumin in 0.9% NaCl at concentrations of 0.133 mg/ml and 2mg/ml respectively, and rinsed with 0.9% NaCl. From each slide two disks were punched out - on from the uncoated surface, the other from the portion coated with collagen or elastin - and the associated radioactivity measured. Compared to PMMA, adsorption of both plasma proteins was strongly reduced (2p <0.001) on collagen and elastin (Table, x±SD, n=10). Low adsorption was more marked for fibrinogen and on the elastin coated surface. Surface peeling could not account for the observed differences, since surface concentrations of fibrinogen did not differ significantly between surfaces exposed for 2 min, 4 min or 2 min followed by a 2 min rinse with 0.9% NaCl.

Conclusion. Results from studies on plasma protein adsorption on synthetic polymers are not necessarily transferable to natural. substrates and, consequently, to the in vivo situation.