Impact of Temperature on the Self-Assembly of Fibrinogen in Thrombin-Free Solutions

Self-assembly of thrombin-free solutions of fibrinogen can be triggered not only by a drop in the ionic strength but also by an appropriate decrease in temperature. Accordingly, an in situ study of self-assembly of fibrinogen in saline buffered solution is carried out by means of time-resolved light scattering providing the molar mass, geometric size, and hydrodynamic radius of the growing intermediates. The resulting data provide access to the morphology of the intermediates and to the mechanism in which these intermediates grow during the early stages of self-assembly. Modeling the results of concentration dependent experiments based on temperature gradients in terms of a chain growth mechanism leads to the corresponding molar standard enthalpy and entropy of aggregation.