Table 3.
Contact angles for ppNIPAM (top), spNIPAM (middle), and blank control surfaces (bottom) at all storage conditions taken above and below the LCST. Control surfaces show no thermoresponse, while ppNIPAM and spNIPAM surface before submersion in DPBS (0hr) were thermoresponsive.
| Contact Angle | ||||||||
|---|---|---|---|---|---|---|---|---|
| 25°C Low Humidity |
25°C High Humidity |
37°C Low Humidity |
37°C High Humidity |
|||||
| 25°C | 37°C | 25°C | 37°C | 25°C | 37°C | 25°C | 37°C | |
| ppNIPAM 0hr | 31.7 σ=6.1 | 42.2** σ=3.8 | 36.4 σ=7.4 | 42.6** σ=5.9 | 32.0 σ=3.3 | 43 4** σ=5.8 | 35.3 σ=3.8 | 43.5** σ=4.7 |
| ppNIPAM 2hr | 35.2 σ=2.6 | 39.4** σ=1.3 | 36.6 σ=8.3 | 43.4** σ=5.9 | 35.6 σ=4.5 | 42.7** σ=1.3 | 33.8 σ=2.8 | 42.7** σ=4.3 |
| ppNIPAM 48hr | 36.7 σ=4.6 | 43.4** σ=2.3 | 36.0 σ=2.8 | 43.7** σ=3.6 | 34.6 σ=4.2 | 41.4** σ=4.3 | 36.6 σ=4.4 | 38.9 σ=1.2 |
| spNIPAM 0hr | 38.8 σ=4.0 | 45.3** σ=2.3 | 42.3 σ=5.8 | 47.8** σ=4.3 | 42.9 σ=6.2 | 47.9* σ=3.0 | 40.0 σ=3.9 | 48.8** σ=5.4 |
| spNIPAM 2hr | 42.3 σ=5.3 | 45.3* σ=4.0 | 40.0 σ=3.1 | 43.3** σ=2.8 | 41.5 σ=5.5 | 44.5* σ=5.1 | 40.6 σ=2.8 | 45.3** σ=2.0 |
| spNIPAM 48hr | 40.9 σ=2.8 | 41.1 σ=4.3 | 40.3 σ=1.7 | 42.0 σ=3.9 | 41.3 σ=2.0 | 35.1■ σ=1.4 | 38.5 σ=3.5 | 34.7■ σ=1.7 |
| Control 0hr | 44.8 σ=1.7 | 47.3 σ=2.8 | 43.9 σ=3.3 | 46.9 σ=2.1 | 45.3 σ=5.4 | 48.7 σ=4.0 | 44.5 σ=6.7 | 48.5 σ=5.6 |
| Control 2hr | 52.7 σ=6.5 | 54.8 σ=5.7 | 49.3 σ=5.1 | 51.2 σ=4.5 | 47.1 σ=4.4 | 51.5 σ=6.9 | 51.1 σ=11.6 | 52.9 σ=5.5 |
| Control 48hr | 30.5 σ=8.6 | 30.4 σ=7.3 | 25.2 σ=3.3 | 28.7 σ=5.3 | 26.7 σ=3.3 | 28.2 σ=3.5 | 26.1 σ=3.0 | 25.3 σ=3.0 |
PpNIPAM surfaces maintained thermoresponse after 48 h in DPBS, while spNIPAM surfaces showed either no thermoresponse or reverse thermoresponse. N = 9, samples marked with ** are very statistically significant (p ≤ 0.006), * statistically significant (p < 0.05), and ■ are statistically significant (p < 0.05) but exhibit a reversed thermoresponse.