Engineering Functionalized
Polymer Microwells for
Selective Stem Cell Adhesion
Sabrina
Montero-Pancera1, Vanessa Trouillet2, Andre Petershans1,3,
Dagmar Fichtner3, Andrey Lyapin5, Michael Bruns2,
Thomas Schimmel4,
Stefan Reichlmaier5, Peter G. Weidler1,
1Institute of Functional Interfaces, 2Institute
of Material Sciences III, 3Zoological Institute II, 4Institute
of Nanotechnology, KIT, 76131
5Physical Electronics GmbH, 85737
A novel, recently patented
method [[1]]
to produce submicro-walled chemically activated polystyrene (PS) microwells by
one-step UV-lithography under ambient conditions which are selectively coated
with gelatin is introduced. The dimensions as well as the shape of the
resulting structures are both tunable merely by the irradiation time through
one and the same mask (see AFM images below of two PS surfaces irradiated for
different times through the same mask). It is shown that the superposition of
radiation induced (i) oxidation, (ii) cross linking and (iii) removal of
polystyrene result in the formation of microscaled, oxidized polymer wells
separated by polymer walls, whereas the polymer walls are formed below the mask structures. The
topographical changes induced by the UV-irradiation are investigated by AFM and
ellipsometry. Chemical characterization is carried out by XPS, fluorescence
microscopy and TOF-SIMS. After the irradiated samples were treated with gelatin
solution it was found, that stem cells selectively attach to the irradiated
areas. This is due to the selective immobilization of the gelatin on the
irradiated polymer areas [[2]].