Table 1. Shear viscosities of phospholipase-resistant synthetic surfactants containing SP-B/C peptides.
Viscosities measured as a function of shear rate are shown for synthetic surfactant suspensions containing 9:1 DEPN-8:PG-1 combined with either 3% (by wt) S-MB DATK, 3% SP-Css ion-lock 1, or 1.5% S-MB DATK + 1.5% SP-Css ion-lock 1 peptides. Viscosities of selected current clinical animal-derived surfactant drugs as formulated are shown for comparison.
| Viscosity (Centipoise) at Different Shear Rates (S−1) | |||||||||
|---|---|---|---|---|---|---|---|---|---|
| Surfactants | 33 | 77 | 225 | 154 | 230 | 307 | 384 | 576 | 768 |
| DEPN-8 | 4.7 ± 0.5 | 3.9 ± 0.5 | 3.2 ± 0.1 | 2.8 ± 0.3 | 2.7 ± 0.2 | 2.6 ± 0.2 | 2.3 ± 0.1 | 2.3 ± 0.1 | 2.3 ± 0.1 |
| DEPN-8:PG-1 | 4.2 ± 0.3 | 3.7 ± 0.4 | 3.4 ± 0.2 | 3.1 ± 0.3 | 2.8 ± 0.1 | 2.8 ± 0.1 | 2.6 ± 0.2 | 2.5 ± 0.1 | 2.5 ± 0.1 |
| DEPN-8:PG (9:1) + 3% S-MB DATK | |||||||||
| 16.7 ± 1.9 | 14.7 ± 1.2 | 11.0 ± 1.7 | 9.2 ± 1.7 | 7.6 ± 1.3 | 5.9 ± 0.9 | 4.5 ± 0.9 | 4.1 ± 0.9 | 3.8 ± 0.8 | |
| DEPN-8:PG (9:1) + 3% SP-Css ion-lock 1 | |||||||||
| 30.2 ± 2.1 | 26.5 ± 2.3 | 20.5 ± 0.8 | 17.2 ± 1.1 | 14.4 ± 0.8 | 10.4 ± 1.2 | 8.9 ± 1.1 | 8.0 ± 1.5 | 6.2 ± 1.7 | |
| DEPN-8:PG (9:1) + 1.5% S-MB DATK + 1.5% SP-Css ion-lock 1 | |||||||||
| 18.7 ± 2.6 | 16.0 ± 2.1 | 11.8 ± 2.3 | 9.8 ± 2.6 | 7.9 ± 1.6 | 6.1 ± 2.0 | 4.4 ± 1.3 | 4.0 ± 1.4 | 3.6 ± 1.4 | |
| Infasurf | 26.9 ± 0.9 | 25.0 ± 0.4 | 19.3 ± 0.3 | 15.8 ± 0.2 | 12.4 ± 0.2 | 10.4 ± 0.2 | 9.1 ± 0.1 | 7.5 ± 0.1 | 6.6 ± 0.1 |
| Survanta | 34.2 ± 2.1 | 28.8 ± 0.4 | 21.1 ± 0.8 | 18.8 ± 0.7 | 15.6 ± 0.4 | 13.7 ± 0.2 | 12.2 ± 0.6 | 9.7 ± 0.1 | 9.1 ± 0.1 |
| Curosurf | 19.5 ± 1.2 | 14.1 ± 2.0 | 12.6 ± 1.8 | 11.6 ± 1.0 | 10.4 ± 1.4 | 9.7 ± 1.2 | 9.2 ± 1.2 | 8.5 ± 1.1 | 8.3 ± 1.0 |
Notes.
See Methods for experimental details. Concentrations of synthetic phospholipase-resistant surfactants were 35 mg lipid/ml, and samples of animal-derived clinical surfactants were as clinically formulated, i.e., Infasurf (35 mg/ml), Survanta (25 mg/ml), and Curosurf (80 mg/ml). All data are Mean ± S.E.M. for N = 4.