TABLE 1.
Mean contact angle measurements, surface Gibbs energies, and energy of interaction for crude and purified suspensions of spores from Geobacillus sp. isolates and inert surfaces
| Surface | Contact angle (°) ± SDa (n = 10)
|
Surface tension component (mJ m−2)
|
|||||||
|---|---|---|---|---|---|---|---|---|---|
| θW | θF | θα-B | γSTOT | γSLW | γSAB | γS+ | γS− | ΔGsls | |
| Crude D4 | 13 ± 2 | 14 ± 2 | 40 ± 4 | 56.4 | 34.6 | 21.8 | 2.2 | 53.1 | 28.8 |
| Pure D4 | 10 ± 2 | 11 ± 2 | 48 ± 4 | 58.3 | 30.7 | 27.5 | 3.6 | 53.4 | 27.0 |
| Crude E7 | 16 ± 1 | 19 ± 1 | 49 ± 2 | 56.0 | 30.6 | 25.3 | 3.0 | 53.6 | 28.6 |
| Pure E7 | 18 ± 1 | 20 ± 3 | 68 ± 5 | 49.4 | 21.0 | 38.4 | 7.2 | 51.4 | 20.1 |
| Crude E11 | 21 ± 2 | 19 ± 1 | 39 ± 2 | 54.6 | 35.1 | 19.6 | 1.9 | 50.0 | 26.4 |
| Pure E11 | 25 ± 3 | 25 ± 2 | 44 ± 1 | 52.5 | 32.1 | 19.7 | 2.0 | 49.8 | 27.3 |
| Crude CGT-8 | 21 ± 3 | 23 ± 3 | 46 ± 4 | 53.6 | 31.8 | 21.8 | 2.3 | 52.4 | 29.1 |
| Pure CGT-8 | 20 ± 3 | 24 ± 4 | 41 ± 7 | 52.8 | 34.1 | 18.7 | 1.6 | 53.5 | 31.4 |
| Stainless steel | 54 ± 10 | 24 ± 7 | 15 ± 3 | 53.8 | 42.9 | 10.9 | 1.8 | 16.5 | −21.7 |
| Thermanox | 63 ± 5 | 17 ± 5 | 8 ± 1 | 53.2 | 43.9 | 9.3 | 3.4 | 6.3 | −40.2 |
| Glass | 1 ± 0 | 7 ± 3 | 40 ± 2 | 58.2 | 34.8 | 23.4 | 2.5 | 54.4 | 29.2 |
a
θF contact angle of formamide; θα-B, contact angle of α-bromonaphthalene.