Table 2.

Comparison of protocols for collagen fibril formation in vitro.

	Neutralizing salt solutions		Culture medium
Composition/ Reference	Williams et al. [16]	Holmes et al. [17]	Elsdale and Bard [93]	Bell et al. [94]	Brown et al. [101]
Concentrations of salts in the final solution	•30 ​mM Na2HPO4 •30 ​mM TES/HEPES∗ •135 ​mM NaCl •NaOH •collagen solution in acetic acid	•62 ​mM Na2HPO4 •14.6 ​mM KH2PO4 •NaOH •collagen solution in acetic acid	•10x Eagle's medium with 10% fetal calf serum •NaOH •collagen solution in 0.1X Eagle's medium	•1.0 ​ml concentrated McCoy's 5a medium •1.0 ​ml serum •0.25 ​ml 0.1 ​M NaOH •1.5 ​ml collagen solution in acetic acid •1.0 ​ml fibroblasts suspended in McCoy's	•0.3 ​ml 10x Eagle minimum essential medium (EMEM) •0.3 ​ml Earle'’s balanced salt solution •5 ​M NaOH •2.4 ​ml Collagen solution in acetic acid
Ionic strength	I ​= ​=0.225	I ​= ​=0.2	–-	–-	–-
pH	7.0–-7.4	7.4	7.6	Neutral (exact value not specified)	Neutral (exact value not specified)
Temperature	26-30 ​°°C	34 ​°°C	Room temperature	37 ​°°C	37 ​°°C
Gelation rate	Relatively slow gelation	Relatively slow gelation	Rapid gelation	Rapid gelation	Rapid gelation