Table 2. Shear rate viscosities of synthetic glycerophospholipid:peptide surfactants as a function of shear rate.
Viscosities measured as a function of shear rate are shown for synthetic lung surfactants containing glycerophospholipids (5:3:2 DPPC:POPC:POPG) combined with either 3% S-MB DATK, 3% SP-Css ion-lock 1, or 1.5% S-MB DATK + 1.5% SP-Css ion-lock 1 peptides.
| Viscosity (Centipoise) at Different Shear Rates (S−1) | |||||||||
|---|---|---|---|---|---|---|---|---|---|
| Surfactants | 33 | 77 | 225 | 154 | 230 | 307 | 384 | 576 | 768 |
| 5:3:2 DPPC:POPC:POPG | |||||||||
| 35 mg/ml | 2.6 ± 0.5 | 1.7 ± 0.2 | 1.6 ± 0.1 | 1.5 ± 0.1 | 1.4 ± 0.1 | 1.4 ± 0.1 | 1.4 ± 0.1 | 1.4 ± 0.1 | 1.4 ± 0.1 |
| 5:3:2 DPPC:POPC:POPG + 3% S-MB DATK | |||||||||
| 35 mg/ml | 5.0 ± 0.2 | 4.3 ± 0.4 | 3.9 ± 0.2 | 3.7 ± 0.2 | 3.6 ± 0.2 | 3.5 ± 0.2 | 3.3 ± 0.2 | 3.1 ± 0.2 | 3.0 ± 0.1 |
| 60 mg/ml | 10.6 ± 0.4 | 9.4 ± 0.8 | 8.8 ± 0.8 | 8.1 ± 0.8 | 7.7 ± 0.8 | 7.1 ± 0.7 | 6.8 ±0.7 | 6.4 ± 0.6 | 6.0 ± 0.6 |
| 5:3:2 DPPC:POPC:POPG + 3% SP-Css ion-lock 1 | |||||||||
| 35 mg/ml | 31.4 ± 3.3 | 26.4 ± 2.2 | 23.0 ± 3.1 | 19.5 ± 3.4 | 16.4 ± 2.9 | 13.9 ± 2.5 | 11.7 ± 2.0 | 9.7 ± 1.6 | 7.7 ± 1.2 |
| 60 mg/ml | 42.2 ± 4.9 | 36.9 ± 5.4 | 30.5 ± 4.6 | 28.6 ± 4.0 | 19.9 ± 1.4 | 18.8 ± 1.7 | 16.8 ± 1.7 | 13.5 ± 3.5 | 11.5 ± 2.7 |
| 5:3:2 DPPC:POPC:POPG + 1.5% S-MB DATK + 1.5% SP-Css ion-lock 1 | |||||||||
| 35 mg/ml | 6.0 ± 0.4 | 4.7 ± 0.5 | 4.2 ± 0.6 | 4.0 ± 0.6 | 3.7 ± 0.6 | 3.6 ± 0.6 | 3.5 ± 0.6 | 3.3 ± 0.6 | 3.2 ± 0.6 |
| 60 mg/ml | 12.7 ± 0.5 | 11.8 ± 0.3 | 10.5 ± 0.3 | 9.2 ± 0.2 | 8.8 ± 0.2 | 7.9 ± 0.2 | 7.5 ± 0.4 | 6.7 ± 0.5 | 6.3 ± 0.6 |
Notes.
See Methods for experimental details, and Table 1 for the viscosities of selected animal-derived clinical surfactants. Data are Mean ± S.E.M. for N = 3–4.