Splitting and switching of microfluid segments in closed channels for chemical operations in the segment-on-demand technology

in: Chemical Engineering Journal (2013)
Budden, Matthias; Schneider, Steffen; Kielpinski, Mark; Henkel, Thomas; Köhler, J. Michael; Gross, G. Alexander
Basic functional units and a preparation technology have been developed for the investigation of segment operations in larger sequences of droplets. A high reproducibility of segment operations with branched micro channel structures (0.3 mm) even up to high flow rates was achieved. A switching of segments was realized by an electrical actuation without galvanic contact. The applied voltages has been in the range between 0.1 and 1.2 kV at distances between electrodes and the fluid channel of about 100 μm resulting in electrical fields in the range of about 0.2 ... 2.4 MV/m. The switching effect cannot be explained by a poor electrowetting or a pure electrostatic effect on the fluid segments, but is caused obviously by a combination of them. A controlled switching with frequencies up to about 5 Hz was realized by a fast optical in-situ measurement and a feed-back loop between the optical measurement channel and the electro actuator. After optical detection, segments can be directed individually to one of two outlet ports. The distance between segments in the both outlet channels is directly determined by the order of switching pulses. So, it is possible to realize an automated sorting of micro fluid segments and to generate arbitrarily defined micro fluid segment patterns. The technique will be applied for the handling of small cell ensembles and single cells for bioassays in screenings at the nanoliter level and for combinatorial screenings in chemistry.

Cookies & Skripte von Drittanbietern

Diese Website verwendet Cookies. Für eine optimale Performance, eine reibungslose Verwendung sozialer Medien und aus Werbezwecken empfiehlt es sich, der Verwendung von Cookies & Skripten durch Drittanbieter zuzustimmen. Dafür werden möglicherweise Informationen zu Ihrer Verwendung der Website von Drittanbietern für soziale Medien, Werbung und Analysen weitergegeben.
Weitere Informationen finden Sie unter Datenschutz und im Impressum.
Welchen Cookies & Skripten und der damit verbundenen Verarbeitung Ihrer persönlichen Daten stimmen Sie zu?

Sie können Ihre Einstellungen jederzeit unter Datenschutz ändern.