Table 1.

The effects of chitosan gelation media, solution concentration, pH on the maintenance of 3D printed structure (gelation process carried out at room temperature).

Gelation media	Concentration	pH	Maintenance of 3D structure	Neutralization time (sec)
KOH	1,5 M	14	✓	30
	1 M	14	✓	50
	0,5 M	13.70	✓	60
	0,1 M	13.13	✗	300
Na2CO3	1,5 M	11.94	✓	40
	1 M	11.74	✓	50
Na2CO3+NaHCO3	0.5 M 0.5 M	9.72	✗	90
Na2CO3+NaHCO3	0.01 M 0.09 M	9.22	✗	n.d.*
Na2CO3+NaHCO3	0.05 M 0.05 M	10.05	✗	240
Na2HPO4 K2HPO4	0.1 M 0.005 M	8.08	✗	n.d.*
Na2HPO4+Citric acid	0.1 M 0.05 M	7.6	✗	n.d.*
Ammonia vapour from 28% aqueous solution		13	✓	18

^*n.d. = not detectable.