Table 1 Friction and stiffness parameters at room temperature for a 1 μm sized bead in aqueous solution depending on the time-averaged penetration distance d to the GUV membrane

From: Thermal fluctuations of the lipid membrane determine particle uptake into Giant Unilamellar Vesicles

Bead friction γbd

Membrane friction γmem (d)

Trap stiffness κopt

Membrane stiffness κmem (d)

Relaxation times bead τtot (d)

Relaxation timea, mode τ(n = 1–10)

Trap dwell time Δt

Membrane bending rigidity K

Membrane surface tension σ

\(8\,\frac{{{{{{{\rm{pN}}}}}}}}{\mu {{{{{\rm{m}}}}}}}{{{{{{\rm{ms}}}}}}}\)

\(0\!-\!8\frac{{{{{{{\rm{pN}}}}}}}}{\mu {{{{{\rm{m}}}}}}}{{{{{{\rm{ms}}}}}}}\)

\(4\!-\!75\frac{{{{{{{\rm{pN}}}}}}}}{\mu {{{{{\rm{m}}}}}}}\)

\(0\!-\!15\frac{{{{{{{\rm{pN}}}}}}}}{\mu {{{{{\rm{m}}}}}}}\)

0.1–0.8 ms

56–0.19 ms

100 ms

1.6–20\({k}_{B}T\)

10–300\(\frac{{k}_{B}T}{{{{{{{\rm{\mu m}}}}}}}^{2}}\)

  1. The surface tension converts as \(250\,{k}_{B}T/{\mu {{{{{\rm{m}}}}}}}^{2}=\,250\cdot (4{{{{{{\rm{pN}}}}}}}\cdot {{{{{{\rm{nm}}}}}}}/{\mu {{{{{\rm{m}}}}}}}^{2})=1\,{{{{{{\rm{pN}}}}}}}/\mu {{{{{\rm{m}}}}}}\,\). Shortest particle relaxation times inside the trap are \({\tau }_{c}={\gamma }_{{bd}}/{\kappa }_{{opt}}\approx 0.1-2\,{{{{{{\rm{ms}}}}}}}\) (lateral xy directions). 100,000 3D particle positions were recorded at each trap position, i.e. within \(\Delta t=100\,{{{{{{\rm{ms}}}}}}}\). aTheoretical values for a GUV with \({R}_{g}=10\,\mu {{{{{\rm{m}}}}}}\), \(K=10\,{k}_{B}T\), \(\sigma=50\,{k}_{B}T/{\mu {{{{{\rm{m}}}}}}}^{2}\).
Back to article page