A plant or an animal cell uses numerous processes to sort and assemble tiny building blocks into larger molecules, to rebuild molecules or to dissolve them. Using synthetic gel particles, scientists try to simulate these cellular procedures; however, mimicking the complexity of natural processes presents a formidable task for scientists.
Researchers from the DWI – Leibniz Institute for Interactive Materials in Aachen and the University of Freiburg now developed a set of four different, micrometer-sized building blocks, which can self-sort and co-assemble into defined compositions and disassemble at the push of a button.
A set of blue, red, green and yellow Lego bricks helps to visualize this research approach. It is very simple to build a multicolored object from these bricks, without considering the colors of the single bricks. To make it slightly more complicated, one could initially sort the bricks by their color and then build objects that are either blue, red, green or yellow.
Such processes are referred to as ‘unsocial assemblies’ if they are driven by themselves. To make things even more complex, you could also build some objects from red and blue bricks and others from green and yellow bricks. These processes, if running simultaneously, are termed ‘social assemblies’.
The scientists from Aachen and Freiburg solved a similar task; however on a microscopic scale by using small gel particles instead of Lego bricks. These so-called microgels are water-rich, sponge-like gel particles, which can be chemically modified.
“We used four different types of microgels for our experiments. The microgels can self-assemble in an ‘unsocial’ manner, staying amongst themselves, or co-assemble in a ‘social’ manner, with a second type of microgel,” explains Dr. Alexander Kühne from DWI. He coordinated this project together with Prof. Dr. Andreas Walther, a former DWI scientist who recently moved to the University of Freiburg.
The challenge of this project was to enable the microgels to distinguish between right and wrong partners. To achieve this, the scientists integrated molecular interactions so that only specific types of microgels would interact with each other – just like a key, which can only open a very specific lock.
However, instead of keys and locks, the researchers applied switchable molecules that integrate into cyclic sugar moieties. Triggered by certain chemical conditions or by light the researchers could control the molecular shape and their interactions during the experiment. This way, the microgels can self-sort, self-assemble and disassemble at the push of a button.
“We use these types of experiments to get a better understanding of processes running in natural cells,” says Alexander Kühne. “In addition, progress in this field of research will eventually help us to develop biologically inspired, interactive materials.”
Publication: Kang Han, Dennis Go, Thomas Tigges, Khosrow Rahimi, Alexander J. C. Kuehne, Andreas Walther, “Social Self-Sorting of Colloidal Families in Co-Assembling Microgel Systems”, Angewandte Chemie International Edition 2017, DOI: 10.1002/anie.201612196.
Dr. Janine Hillmer | idw - Informationsdienst Wissenschaft
Numbers count in the genetics of moles and melanomas
16.08.2019 | University of Queensland
Working out why plants get sick
16.08.2019 | Institut für Pflanzenbiochemie
Soft robots have a distinct advantage over their rigid forebears: they can adapt to complex environments, handle fragile objects and interact safely with humans. Made from silicone, rubber or other stretchable polymers, they are ideal for use in rehabilitation exoskeletons and robotic clothing. Soft bio-inspired robots could one day be deployed to explore remote or dangerous environments.
Most soft robots are actuated by rigid, noisy pumps that push fluids into the machines' moving parts. Because they are connected to these bulky pumps by tubes,...
Researchers at TU Graz are working together with European partners on new possibilities of measuring vehicle emissions.
Today, air pollution is one of the biggest challenges facing European cities. As part of the Horizon 2020 research project CARES (City Air Remote Emission...
Over the next three years, researchers from the Vrije Universiteit Brussel, University of Cambridge, École Supérieure de Physique et de Chimie Industrielles de la ville de Paris (ESPCI-Paris) and Empa will be working together with the Dutch Polymer manufacturer SupraPolix on the next generation of robots: (soft) robots that ‘feel pain’ and heal themselves. The partners can count on 3 million Euro in support from the European Commission.
Soon robots will not only be found in factories and laboratories, but will be assisting us in our immediate environment. They will help us in the household, to...
Scientists at the University of Leeds have created a new form of gold which is just two atoms thick - the thinnest unsupported gold ever created.
The researchers measured the thickness of the gold to be 0.47 nanometres - that is one million times thinner than a human finger nail. The material is regarded...
An international team of scientists involving the Max Planck Institute for the Structure and Dynamics of Matter (MPSD) in Hamburg has unraveled the light-induced electron-localization dynamics in transition metals at the attosecond timescale. The team investigated for the first time the many-body electron dynamics in transition metals before thermalization sets in. Their work has now appeared in Nature Physics.
The researchers from ETH Zurich (Switzerland), the MPSD (Germany), the Center for Computational Sciences of University of Tsukuba (Japan) and the Center for...
16.08.2019 | Event News
14.08.2019 | Event News
12.08.2019 | Event News
16.08.2019 | Life Sciences
16.08.2019 | Physics and Astronomy
16.08.2019 | Medical Engineering