Biological fluids are typically composed of water with a range of dispersed proteins, polysaccharides, and biopolymers.  This dispersed components impart uniqued rheological behaviors that have a major impact on the functionality of these solutions. 

In recent years, the study of globular proteins has found a wide range of interesting behaviros such as high elasticity, yield and rheopexy at low protein concentrations.  Recent work done in our lab and others have shown that these behaviors are actual due to the interfacial rheology of proteins adsorbed to the interface.

Once interfacial effects are removed, the true rheology of the systems can be studied.  We have begun to characterize synovial fluid, the lubricating liquid in knees in both small and large amplitude oscillatory shear in order to understand its function under stresses and strain representative of human motion.

  1. Zhang, Z. et al. "LAOS of Model Synovial Fluids," In Preperation.
  2. Zhang, Z. et al. "The Role of Protein Content on the Steady and Oscillatory Shear Rheology of Model Synovial Fluids," Soft Matter. Submitted.
  3. Zhang, Z. et al. "Effect of Interfacial Viscoelasticity on the Bulk Linear viscoelastic Moduli of Globular Protein Solutions," Physical Review E, 2013. 89