Methacrylate conjugated bovine collagen type 1 ma col

Methacrylate-conjugated bovine collagen type I (MA-COL; Advanced BioMatrix, Carlsbad, CA, USA) was reconstituted in sterile 20 mM acetic acid to achieve 6 mg/ml. Immediately prior to use, 1 ml MA-COL was neutralized with 85 μl neutralization buffer (Advanced BioMatrix) according to the manufacturer’s instructions. Thiol-conjugated hyaluronic acid (SH-HA; Glycosil^®; Advanced BioMatrix) was reconstituted in sterile diH2O containing 0.5% (w/v) photoinitiator (4-(2-hydroxyethoxy) phenyl-(2-propyl) ketone; Irgacure^® 2959; Sigma-Aldrich) to achieve 10 mg/ml according to the manufacturer’s protocol. In-house expressed ELP (SH-ELP; thiol via KCTS flanks ^{46 (link),51 (link)}) was reconstituted in chilled DPBS to achieve 10 mg/ml and sterilized using a 0.2 μm syringe filter in the cold.

Methacrylate-conjugated bovine collagen type I (MA-COL; molecular weight: ~300 kDa, degree of methacrylation: ~60–70%; Advanced BioMatrix, Carlsbad, CA, USA) was reconstituted according to the manufacturer’s instructions with sterile 20 mM acetic acid at 4 mg/ml; 1 ml MA-COL was neutralized with 90 μl neutralization buffer (Advanced BioMatrix) for hydrogel use. Thiol-conjugated hyaluronic acid (SH-HA; Glycosil®; molecular weight: ~300 kDa, degree of thiolation: ~20–30%; Advanced BioMatrix) was reconstituted in sterile diH2O at 10 mg/ml according to the manufacturer’s instructions.