Mass release of GelMA, GelMA/DbPE and GelMA/TbPE hydrogels was monitored over a period of 14 days. 200 µL precursor solution was transferred onto a PDMS surface and photocrosslinked by UV light irradiation (302 nm, 8 W). Following lyophilization, dry weight was measured, and samples were incubated in DPBS at 37 °C. The DPBS solution was exchanged every 2-3 days. After 0, 1, 2, 4, 7, 10, and 14 days, hydrogel samples were lyophilized and weighed after carefully removing residual water from the surface. The remaining mass was calculated from the following equation, where 𝑤 + is the initial dry weight and 𝑤 , is the dry weight at time t.