Every sample can be quite unique depending on what it is formulated of. In general, we have seen most proteins to show non-Newtonian behavior. As most samples are, proteins are quite complex and when it comes to being in formulation, manufacturing, or just in general a Protein Scientists, you may see this uphill battle where you need to reduce the viscosity of the proteins, while maintaining efficacy, and also reducing as much of the physical contributions injecting your proteins could have to a patient.
When a sample shows non-Newtonian behavior, it is recommended to test the sample at a wide shear rate range (at least 25%, 50%, and 75% full scale with RheoSense viscometers). Some proteins may actually show shear thinning behavior at much higher shear rates, while other proteins show a nice shear thinning curve over standard shear rates. It is all different so it is important for you to review and understand the scope and behavior of your special protein.
To learn about the differences between Newtonian vs. non-Newtonian, check out our educational page here: https://www.rheosense.com/applications/viscosity/newtonian-non-newtonian
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