Surfactant Effects on Adsorption of Recombinant Factor VIII (rFVIII) at the Air-Water Interface

The primary goal was to characterize the adsorption of a recombinant therapeutic protein\ud in the presence of selected surfactant species at the air-water interface. For this purpose,\ud dynamic interfacial tensiometry was used to determine the surface tension kinetics\ud exhibited by protein solutions containing either Tween 80 or the poly[ethylene oxide]-\ud poly[propylene oxide]-poly[ethylene oxide] triblock copolymer surfactant, Pluronic®\ud F68. Tween 80 is widely used in downstream processing and formulation, while F68 is\ud widely used upstream in cell culture for its protective effect on mammalian cells. Very\ud low protein concentrations were used in order to represent conditions consistent with cell\ud culture operations. The apparent effect of each surfactant on protein adsorption was\ud determined to be strongly dependent on surfactant concentration. While F68 appeared to\ud be more effective at reducing protein adsorption at extremely low surfactant\ud concentrations, Tween 80 appeared to be much more effective at higher surfactant\ud concentration. Conclusions point to the opportunity to optimize surfactant use in\ud upstream and downstream processing in biotechnology, where surfactant design or\ud selection might be based on ensuring protein stability and activity retention by\ud simultaneous use of surfactants which act according to complementary stabilization\ud mechanisms