Fig. 2: StemBond improves cell attachment to soft hydrogels.

a mESC attachment on sulfo-SANPAH functionalised standard PAAm hydrogels (left) and StemBond hydrogels (right). Cells were counted after 48 h in serum+LIF (n = 2–6 independent samples). P-values from ANOVA with Tukey–Kramer’s multiple comparison test comparing Low AHA to Mid AHA and High AHA, and sulfo–SANPAH hydrogels to StemBond hydrogels globally. Stiffness was not a significant factor (p = 0.58). Bars show mean ± standard deviation, points show the value independent samples. b Representative brightfield images of cells after 24 h in serum + LIF on tissue culture plastic (TCP), stiff and soft StemBond hydrogels with different adhesiveness (AHA concentrations). Scale bar: 100 µm. c hPSC attachment on soft and stiff sulfo-SANPAH functionalised standard PAAm hydrogels and high AHA StemBond hydrogels, with laminin 521 or vitronectin coating. Cells were counted after 4 days in E8 media (n = 3 independent experiments). P-values were computed using a one-way ANOVA with Tukey–Kramer’s multiple comparison test, comparing sulfo-SANPAH functionalised to StemBond hydrogels for each stiffness and ECM protein. On soft substrates, only Laminin on StemBond yielded enough cells, other conditions yielded very little cells, below the range of the cell counter. Error bars show standard deviation, points show the value independent repeats. d Representative brightfield images of hPSC colonies attached to laminin 521 and vitronectin coated StemBond hydrogels at day 4 of seeding (day 2 for TCP). Cells were grown in E8 media with ROCK inhibitor for the first 24 h. Scale bar: 50 µm. Source data are provided as a Source Data file.