Table 1.
Experimental conditions for SFS measurements.
| testing variables | length, L a (μm) | AFM cantilever stiffness (N m−1) | ramp sizeb (nm) | velocity (μm s−1) | triggerc (nm) |
|---|---|---|---|---|---|
| small forces (<10 nN) | 20–50 | 0.018–0.045 | 3000–5000 | 0.05–41.9 | 10–150 |
| large forces (>500 nN) | 21–62 | 8.9 | 5000–20 000 | 5–20 | 60–none |
a
The position of the cantilever on the hair is essential for the calculation of the torque.
b
Ramp size is the maximum distance that the sample can travel vertically when a single force–distance curve is measured. Ramp sizes had to be very large to ensure that the cantilever loses contact with the hair between measurements.
c
The trigger defines the maximum deflection of the cantilever when recording a force–distance curve.