In a gas contactor membrane, gas is transferred between a liquid and a gas through a microporous membrane. The main challenge is to achieve a high gas transfer while preventing wetting and clogging of the membrane. Especially low surface tension liquids and deposits of biological material like proteins and cells pose problems to conventional gas membranes. With regard to heart-lung machines, a good blood-membrane haemocompatibility is also required. To meet these challenges we developed novel membranes based on macroporous metal meshes coated with a super liquid-repellent — or superamphiphobic — layer[1]. The superamphiphobic layer consists of a fractal-like network of fluorinated silicon oxide nanospheres[2]; gas trapped between the nanospheres keeps the liquid from contacting the wall of the membrane. We demonstrate the capabilities of the membrane by capturing carbon dioxide gas into a basic aqueous solution and calculate the mass transfer coefficient. In addition we oxygenate blood, like in heart-lung machines. Usually, blood tends to clog membranes because of the abundance of blood cells, platelets, proteins and lipids. We show that human blood stored in a superamphiphobic well for 24 h can be poured off without leaving cells or adsorbed protein behind.
[1] M. Paven, P. Papadopoulos, S. Schöttler, X. Deng, V. Mailänder, D. Vollmer, H.-J. Butt, Nat. Commun. 2013, 4, DOI 10.1038/ncomms3512.
[2] X. Deng, L. Mammen, H.-J. Butt, D. Vollmer, Science 2012, 335, 67–70.
paven@mpip-mainz.mpg.de
