Abstract EN:

High-throughput cell-based assays require small sam pie volumes to reduce assay costs and to allow for rapid sample manipulation. However, further miniaturization of conventional microtiter plate technology is problematic due to evaporation and capillary action. To overcome these limitations, we have developed a two-phase microfluidic platform in which human cells and multicellular organisms can be cultivated for several days in aqueous microcomparments separated by an inert perfluorocarbon carrier oil. Furthermore, we focused on the automated generation of chemically-dictinct microcompartment to exploit the technology for screening purposes. Ln particular, we interfaced an autosampler with our microfluidic platform sequentially loading compounds from microtiter plates into a length of tubing. Ali compounds are loaded in form of aqueous plugs (nanoliter volumes) separated by fluorinated oil. The resulting array of plugs can be split into multiple small volume copies which can be used as replicates for the same assay as weil as for different assays. Moreover, each array of plugs can be injected into a microfluidic chip for further manipulation. Since the order of the compounds and thus their identity is known throughout the whole screening procedure, the system does not require direct compound labelling. Furthermore, each individual plug can be monitored over time, thus allowing the recording of kinetic data. In the last part of the work we focussed on the development of a novel assay coupling a positive fluorescence signal with the inhibition of viral transduction. This should ultimately allow the screening of antivirals in the previously developed microfluidic systems.