TY  - JOUR
A1  - Sechi, Antonio
A1  - Freitas, Joana M. G.
A1  - Wünnemann, Patrick
A1  - Töpel, Alexander
A1  - Paschoalin, Rafaella Takehara
A1  - Ullmann, Sabrina
A1  - Schröder, Ricarda
A1  - Aydin, Gülcan
A1  - Rütten, Stephan
A1  - Böker, Alexander
A1  - Zenke, Martin
A1  - Pich, Andrij
T1  - Surface-Grafted Nanogel Arrays Direct Cell Adhesion and Motility
JF  - Advanced materials interfaces
N2  - It has long been appreciated that material chemistry and topology profoundly affect cell adhesion and migration. Here, aqueous poly(N- isopropyl acrylamide) nanogels are designed, synthesized and printed in form of colloidal arrays on glass substrates using wrinkled polydimethylsiloxane templates. Using low-temperature plasma treatment, nanogels are chemically grafted onto glass supports thus leading to highly stable nanogel layers in cell culture media. Liquid cell atomic force microscopy investigations show that surface-grafted nanogels retain their swelling behavior in aqueous media and that extracellular matrix protein coating do not alter their stability and topography. It is demonstrated that surface-grafted nanogels could serve as novel substrates for the analysis of cell adhesion and migration. Nanogels influence size, speed, and dynamics of focal adhesions and cell motility forcing cells to move along highly directional trajectories. Moreover, modulation of nanogel state or spacing serves as an effective tool for regulation of cell motility. It is suggested that nanogel arrays deposited on solid surfaces could be used to provide a precise and tunable system to understand and control cell migration. Additionally, such nanogel arrays will contribute to the development of implantable systems aimed at supporting and enhancing cell migration during, for instance, wound healing and tissue regeneration.
Y1  - 2016
U6  - https://doi.org/10.1002/admi.201600455
SN  - 2196-7350
VL  - 3
PB  - Wiley-Blackwell
CY  - Hoboken
ER  - 
TY  - JOUR
A1  - Schürings, Marco-Philipp
A1  - Nevskyi, Oleksii
A1  - Eliasch, Kamill
A1  - Michel, Ann-Katrin
A1  - Liu, Bing
A1  - Pich, Andrij
A1  - Böker, Alexander
A1  - von Plessen, Gero
A1  - Wöll, Dominik
T1  - Diffusive Motion of Linear Microgel Assemblies in Solution
JF  - Polymers
N2  - Due to the ability of microgels to rapidly contract and expand in response to external stimuli, assemblies of interconnected microgels are promising for actuation applications, e.g., as contracting fibers for artificial muscles. Among the properties determining the suitability of microgel assemblies for actuation are mechanical parameters such as bending stiffness and mobility. Here, we study the properties of linear, one-dimensional chains of poly(N-vinylcaprolactam) microgels dispersed in water. They were fabricated by utilizing wrinkled surfaces as templates and UV-cross-linking the microgels. We image the shapes of the chains on surfaces and in solution using atomic force microscopy (AFM) and fluorescence microscopy, respectively. In solution, the chains are observed to execute translational and rotational diffusive motions. Evaluation of the motions yields translational and rotational diffusion coefficients and, from the translational diffusion coefficient, the chain mobility. The microgel chains show no perceptible bending, which yields a lower limit on their bending stiffness.
KW  - microgels
KW  - linear assemblies
KW  - in situ fluorescence microscopy
KW  - shape analysis
KW  - rotational diffusion
KW  - translational diffusion
KW  - bending stiffness
KW  - actuation
Y1  - 2016
U6  - https://doi.org/10.3390/polym8120413
SN  - 2073-4360
VL  - 8
PB  - MDPI
CY  - Basel
ER  -