Table 1. Mechanical Properties of Cantilevers.

type of cantilever	L (μm)a	k (pN/nm)b	fc (kHz)c	Qc	τcalc (μs)d	τ (μs)e
Long BioLever	100	4.3	1.2 ± 0.1	0.32 ± 0.02	86	450f
Modified BioLever Mini	38	4.7	4.1 ± 0.1	0.325 ± 0.004	25	53f
BioLever Fast	9	130	444 ± 2	0.847 ± 0.003	0.6	0.4
Stiff modified BioLever Fast	9	40	240 ± 6	0.52 ± 0.01	0.7	1.2
Soft modified BioLever Fast	9	20	175 ± 3	0.43 ± 0.01	0.8	1.8

^aTypical length provided by manufacturer.

^bSpring constant measured for each cantilever as described in Supporting Information.

^cExtracted from a fit of the simple harmonic oscillator equation to the power spectral densities measured 50 nm above the surface in liquid.

^dτ_calc ≅ (Q/πf_c).³⁴ However, this metric should be used with caution since it differed substantially from the measured relaxation time τ.

^eMeasured τ determined from exponential fit to the tip–sample detachment during SMFS experiments.

^fSee ref (31).