Investigating the Thermodynamics Underlying Monosaccharide-Mediated Collagen Polymerization for Materials Design

Abstract

The use and incorporation of type I collagen (COL) in biomaterials and regenerative medicine have remained challenging due to COL’s ability to spontaneously polymerize at physiological pH in vitro. Previous work has shown that the addition of monosaccharides can delay COL polymerization and increase its solubility under neutral conditions by three orders of magnitudetwo features that enable structure retention and integration into pre-existing fibrous networks. We expand on these findings and describe the thermodynamic effects of these monosaccharides on the growth phase of COL polymerization. We derive van’t Hoff plots for each experimental condition and use these data to support an indirect mechanism for delayed COL assembly profiles based on solvent ordering. We observe that the presence of monosaccharides in a COL solution neither altered nor permanently inhibited the formation of COL fibrils. Finally, we demonstrate the utility of our findings through a proof-of-concept study which showed how the presence of these monosaccharides aided in the delivery of a high (2 mg/mL) concentration of neutralized, monomeric COL into simple patterns without disrupting COL structure formation. Our findings support the application of entropy-regulating systems such as monosaccharides in manipulating the dynamics of some self-assembling proteins to aid in biomaterials design.

Illuminating assembly dynamics regulating short-range order optics in extremely long-lived proteins

“…Our results have demonstrated the ability to control COL assembly at relatively high concentrations, up to 5 mg mL -1 , using monosaccharides at neutral pH, without harsh solvents, and without damaging the native fibrillar architecture or self-assembling function of COL. We tested the utility of the increased lag phase through a proof-of-concept experiment, creating patterns of polymerized proteins (Figure 6.4). 608 We were able to use 0.2M Gal to extend the lag phase of COL assembly, making it easy to setup our apparatus and extrude the COL-Gal mixture onto a glass cover slip. Considering our results estimate a nearly 2-hour window to perform this experiment, we believe this method could be widely applicable in many other contexts for greater degrees of control and scalability.…”