Kinetics of collagen fibril assembly.

<p>(A) Turbidity increases significantly as collagen self-assembles into fibrils. Experiments were conducted for a collagen concentration of 0.5 mg/ml (pH = 6.9 and 21°C). Open circles and error bars represent means and standard deviations from 3 replicate measurements. Inset schematics illustrate that the system begins as triple helical collagen molecules (more flexible than the rod-like schematic) and ends with well-ordered collagen fibrils (of which one small part is shown) that form a gel. (B) TEM image of a self-assembled collagen fibril formed under these conditions, showing the dark-light “D-banding” pattern expected for well-ordered fibrils.