Fraunhofer researchers have reduced testing times for drug ingredients on biological cells by 50 to 80 per cent by combining two microscopy techniques. The prototype system, developed by scientists at Fraunhofer Institute for Production Technology (IPT), consists of two integrated modules: an optical tweezer system and a digital holographic microscope, which enables researchers to study cell interactions more efficiently with fewer measurements.
When developing new medicines, biologists and pharmacologists test different active ingredients and chemical compounds. The main purpose is to find out how biological cells react to these substances.
To do so, researchers often use a fluorescence microscope that produces computer generated holograms in which the cells being studied can be viewed in three dimensions. This means researchers don’t have to use markers to make the cells visible, and they can examine the cells in vivo.
The new technique combines digital holographic microscopy with the use of optical tweezers.
‘By combining these two instruments, we can save between 50 and 80 per cent of the time normally needed for such work, depending on the type of cell and the test method employed. That’s mainly because we don’t have to carry out so many repeated measurements,’ explained IPT group manager Stephan Stürwald.
Optical tweezers are a special instrument that uses the force of a focused laser beam to trap and move microscopic objects. This tool enables the researchers to pick up selected cells, transfer them to individual wells of a microarray, and keep them trapped there.
The combination of these two techniques not only simplifies current test procedures but also allows new tests to be developed. For instance, it is possible to position cells at a defined distance from one another, thus creating different patterns. In this way, the scientists will be able to observe cell interactions, because the spacing between them is identical and fixed. The new system will also enable the user to destroy cells selectively that are unsuitable for testing.
Successful initial tests have already been conducted by the researchers using the new system.
