VWF extension slightly depends on pH from 6.2 to 9.8. VWF multimer extension normalized to length during the first 1280 dyn cm−2 flow (L0, color key) vs. wall shear stress under forward (solid lines) and backward (dash lines) flow following pH 7.4 -> 6.2 -> 7.4 (a, N=35 multimers) or pH 7.4 -> 9.8 -> 7.4 (b, N=38 multimers) buffer exchanges. Black solid lines and the black dashed lines in (A) and (B) are the average and the standard deviation of the extension of individual molecules. They are also overlaid as blue, green and magenta lines in (C) and (D), to aid in comparing the results from indicated buffer exchanges. (E) Percentage of VWF compaction in pH 5.4 to 9.8 buffer.