Send to

Choose Destination
Nano Lett. 2006 Mar;6(3):398-402.

Cellular unbinding forces of initial adhesion processes on nanopatterned surfaces probed with magnetic tweezers.

Author information

Max-Planck-Institute for Metals Research, Department New Materials and Biosystems, Heisenbergstrasse 3, D-70569 Stuttgart, Germany.


To study the dependence of unbinding forces on the distance of molecularly defined and integrin specific c(-RGDfK-) ligand patches in initial cellular adhesion processes, we developed a magnetic tweezers setup for applying vertical forces of up to 200 pN to rat embryonic fibroblasts. The ligand patch distance is controlled with a hexagonally close packed pattern of biofunctionalized gold nanoparticles prepared by block-copolymer micelle nanolithography. Each gold nanoparticle potentially activates up to one alpha(v)beta(3)-integrin. The distances between the gold nanoparticles determine the separation of individual integrins and thus the assembly of integrin clusters. The results show an increase in cellular unbinding forces from approximately 6 to more than 200 pN for a decreasing ligand distance of 145 to 58 nm after 5 min of cell adhesion. Furthermore, we observe a strong dependence on adhesion time during the first 10 min of cell surface contact suggesting an active, cooperative cell response that is controlled by the spacing between individually activated integrins.

[Indexed for MEDLINE]

Supplemental Content

Full text links

Icon for American Chemical Society
Loading ...
Support Center