Table 1.

Several parameters of recently developed nature-derived photocrosslinkable biomaterials for 3D printing

Major biomaterial(s)		Photoinitiator	Curing parameter		Shape fidelity		Printing resolution	Printing method /Construct size	Cell type	Reference
			Intensity [mW /cm2]	Curing time [sec]	Compressive modulus	Storage modulus
UV light-based	HAMA & GelMA	Irgacure 2959	N/A	30, 90	~ 9 kPa	N/A	800 μm	Extrusion /10 mm × 10 mm × 1.2 mm	BAP, WAP	33
	PECMA	Irgacure 2959	7	160	N/A	~ 2.6 kPa	N/A	Extrusion /8 mm × 8 mm × 4.5 mm	hNDFs	35
	SilMA	LAP	30	4	~ 125 kPa	~ 25 kPa	66 μm (circle) 90 μm (square) 142 μm (height)	Light-assisted /25 mm × 25 mm × 50 mm	Chondrocyte	5
	Collagen	Riboflavin	1200	10	N/A	~ 2 kPa	900–1100 μm	Extrusion /25 mm × 25 mm × 0.4 mm	Chondrocyte	39
	dECM	Riboflavin	30	180	~ 15 kPa	10–30 kPa	114–860 μm	Extrusion /N/A	CPCs	41, 44
Visible light-based	Aneroin	Ru(II)bpy32+	2000	10	~ 6400 kPa	N/A	100–950 μm	Extrusion /35 mm × 50 mm × 18 mm	MSCs	12
	Gtn-HPA	Ru(II)bpy32+	N/A	10, 20, 30	~ 55 kPa	N/A	N/A	Extrusion /N/A	COS-7	49

Abbreviation: HAMA methacrylated hyaluronic acid, GelMA methacrylated gelatin, PECMA Pectin methacrylate, SilMA chemically modified silk fibroin by glycidyl methacrylate; dECM decellularized extracellular matrix, Aneroin, sea anemone-derived silk-like protein, Gtn-HPA gelatin-hydroxyphenylpropionic acid conjugate LAP lithium phenyl(2,4,6-trimethylbenzoyl) phosphinate, N/A not available, BAP brown adipose progenitor cells, WAP white adipose progenitor cells, hNDFs human neonatal dermal fibroblasts, CPCs cardiac progenitor cells, MSCs mesenchymal stem cells; COS-7 kidney cells derived from the African green monkey