Parameters	Variations	Results/effects
Temperature	37°C	Well cured for 1.5% collagen
	4°C	Difficult to solidify
	Room temperature	Difficult to solidify
pH	pH 5–6	Difficult to solidify, large pore size (~200 μm)
	pH 6–7	Weakly cured, medium pore size (~120 μm)
	pH 7–8	Well cured, small pore size (~80 μm)
Collagen stock concentration	1.0% (w/v)	Gelation takes a long time (~48 hours), relatively large pore size (∼200 μm)
	1.5% (w/v)	Relatively large pore size (~200 μm)
	2.0% (w/v)	Nonhomogenous gelation, relatively small pore size (~100 μm)
	2.5% (w/v)	Nonhomogeneous gelation, relatively small pore size (~100 μm)
Curing duration	~30 minutes	Less cured for 1.5% collagen
	~60 minutes	Well cured for 1.5% collagen
	~90 minutes	Well cured for 1.5% collagen, susceptible to drying of hydrogel