VP is released from sVPM in pH-sensitive manner, with the fastest release at pH 6.5 and slowest at pH 5.0. (A) Release of VP from sVPM at 37oC at 1, 3, 5, and 12 hour timepoints in buffers prepared to pH 7.4, 6.5, and 5.0 (n=3, mean ± SD), and (B) statistical comparisons between pH at each timepoint (Two-way ANOVA with Tukey post-hoc test).