What effects do new drugs have on the human body – particularly at cellular level? Can doctors administer them without risk, or do they have toxic side effects? Pharmaceutical companies carry out a variety of toxicity tests on new drugs in order to answer such questions. Cell cultures form the basis for these tests: The researchers place isolated cells in small plastic dishes, add a nutrient solution and place the dishes in an incubator heated to 37 degrees Celsius.
To provide an ideal breeding ground for the cells, the dishes are made of insulating polystyrene. Once the cells have multiplied to the required number, the drug is added. However, to examine the cells’ reaction to the drug, the researchers then have to remove the cultured cells from the dish. The problem is that the cells often adhere so firmly to the surface of the dish that an enzyme has to be introduced to detach them. “The cells employed in toxicity tests are particularly sensitive, and can be damaged by the added enzyme. This makes it difficult to interpret the test results. It cannot be established without doubt whether the cells’ reaction to the drug has been influenced by damage caused by the method used to extract them from the dish” says Dr. Claus Duschl, department head at the Fraunhofer Institute for Biomedical Engineering IBMT in Potsdam-Golm.
A possible solution is the stimuli-responsive polymer developed by a team led by Dr. Jean-François Lutz of the Fraunhofer Institute for Applied Polymer Research IAP, assisted by colleagues at the IBMT and the Max Planck Institute of Colloids and Interfaces. “At 37 degrees Celsius, the usual incubation temperature for cell cultures, this material is water-repellent (hydrophobic) – the cells feel at ease in this environment and respond by multiplying rapidly. If the substrate is cooled to 25 degrees, equivalent to room temperature, the material becomes hydrophilic (attracts water): The cells try to avoid contact with the substrate by reducing their surface area, curling up into almost spherical shapes. This enables them to be rinsed off easily, so there is no longer any need to add an enzyme,” explains Lutz.
This is not the first thermoresponsive polymer. The big difference is that it is based on polyethylene glycol (PEG), which unlike other materials of this type is biocompatible. It is thus an ideal substrate for cell cultures. The new material has the added advantage of being water-soluble and non-toxic. Lutz estimates that it will be possible to mass-produce Petri dishes coated with the new property-changing polymer in about two or three years’ time.
Dr. Jean-Francois Lutz | Fraunhofer-Gesellschaft
Seeing on the Quick: New Insights into Active Vision in the Brain
15.08.2018 | Eberhard Karls Universität Tübingen
New Approach to Treating Chronic Itch
15.08.2018 | Universität Zürich
Scientists develop first tool to use machine learning methods to compute flow around interactively designable 3D objects. Tool will be presented at this year’s prestigious SIGGRAPH conference.
When engineers or designers want to test the aerodynamic properties of the newly designed shape of a car, airplane, or other object, they would normally model...
Researchers from TU Graz and their industry partners have unveiled a world first: the prototype of a robot-controlled, high-speed combined charging system (CCS) for electric vehicles that enables series charging of cars in various parking positions.
Global demand for electric vehicles is forecast to rise sharply: by 2025, the number of new vehicle registrations is expected to reach 25 million per year....
Proteins must be folded correctly to fulfill their molecular functions in cells. Molecular assistants called chaperones help proteins exploit their inbuilt folding potential and reach the correct three-dimensional structure. Researchers at the Max Planck Institute of Biochemistry (MPIB) have demonstrated that actin, the most abundant protein in higher developed cells, does not have the inbuilt potential to fold and instead requires special assistance to fold into its active state. The chaperone TRiC uses a previously undescribed mechanism to perform actin folding. The study was recently published in the journal Cell.
Actin is the most abundant protein in highly developed cells and has diverse functions in processes like cell stabilization, cell division and muscle...
Scientists have discovered that the electrical resistance of a copper-oxide compound depends on the magnetic field in a very unusual way -- a finding that could help direct the search for materials that can perfectly conduct electricity at room temperatur
What happens when really powerful magnets--capable of producing magnetic fields nearly two million times stronger than Earth's--are applied to materials that...
The quality of materials often depends on the manufacturing process. In casting and welding, for example, the rate at which melts solidify and the resulting microstructure of the alloy is important. With metallic foams as well, it depends on exactly how the foaming process takes place. To understand these processes fully requires fast sensing capability. The fastest 3D tomographic images to date have now been achieved at the BESSY II X-ray source operated by the Helmholtz-Zentrum Berlin.
Dr. Francisco Garcia-Moreno and his team have designed a turntable that rotates ultra-stably about its axis at a constant rotational speed. This really depends...
08.08.2018 | Event News
27.07.2018 | Event News
25.07.2018 | Event News
15.08.2018 | Physics and Astronomy
15.08.2018 | Materials Sciences
15.08.2018 | Life Sciences