TY  - JOUR
A1  - Liu, Bing
A1  - Böker, Alexander
T1  - Measuring rotational diffusion of colloidal spheres with confocal microscopy
JF  - Soft matter
N2  - We report an experimental method to measure the translational and rotational dynamics of colloidal spheres in three dimensions with confocal microscopy and show that the experimental values reasonably agree with the theoretical values. This method can be extended to study rotational dynamics in concentrated colloidal systems and complex bio-systems.
Y1  - 2016
U6  - https://doi.org/10.1039/c6sm01082b
SN  - 1744-683X
SN  - 1744-6848
VL  - 12
SP  - 6033
EP  - 6037
PB  - Royal Society of Chemistry
CY  - Cambridge
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  -