Table 1.
Effect of PAMAM auxiliaries on the Ts of bovine collagen powder cross-linked with EDC/NHS.
| Entry | Dendrimer | Molecular Weight | PAMAM NH2 | COOHcoll/NH2 a (mol/mol) | Ts (°C) |
|---|---|---|---|---|---|
| 1 | - | - | - | 1.2/0.8 | 80 |
| 2 | 2G0.0 | 516.4 | 4 | 1.2/2.0 | 85 |
| 3 | 3G0.0 | 586.8 | 4 | 1.2/2.0 | 85 |
| 4 | 4G0.0 | 672.0 | 4 | 1.2/2.0 | 87 |
| 5 | 2G1.0 | 1429.9 | 8 | 1.2/3.2 | 95 |
| 6 | 3G1.0 | 1612.2 | 8 | 1.2/3.2 | 87 |
| 7 | 4G1.0 | 1794.6 | 8 | 1.2/3.2 | 80 |
| 8 | 2-Triet-G0.0 | 673.9 | 5 | 1.2/2.3 | 90 |
| 9 | 2-Triet-G1.0 | 1815.3 | 10 | 1.2/3.8 | 80 |
Reaction Conditions: 300 mg of collagen (0.36 mmol of COOHcoll), 30 mL water, pH 5.5, reaction time: 4h, temperature: 25 °C, COOHcoll/EDC/NHS (mol/mol/mol): 1/2/2. a For 1g of collagen corresponding to 1.2 mmoles of -COOH and 0.8 mmoles of NH2, were added 0.09 mmol of PAMAM dendrimer. The amount of free NH2 functional groups is the sum of the peripherical NH2 in the dendrimer and the NH2 in the collagen protein.