Cytocompatibility of SMPs. There is evidence of increasing metabolic activity, prominently 72 h after cell introduction, but some samples show evidence of metabolic activity increasing just 48 h after cell seeding. Samples that are cytotoxic have little metabolic activity as compared to samples that are cytocompatible, confirming a lack of HUVEC presence. Significance was determined using one-way ANOVA to determine significant differences between samples of a given wt % ratio and crosslinker combination, in addition to the Tukey’s Honest Significance Difference Procedure between individual samples. * corresponds to p < 0.05, ** corresponds to p < 0.01, *** corresponds to p < 0.001.