RESUMEN
During fermentation processes, in situ product recovery (ISPR) using submerged membranes allows a continuous operation mode with effective product removal. Continuous recovery reduces product inhibition and organisms in the reactor are not exposed to changing reaction conditions. For an effective in situ product removal, submerged membrane systems should have a sufficient large membrane area and an anti-fouling concept integrated in a compact device for the limited space in a lab-scale bioreactor. We present a new membrane stirrer with integrated filtration membranes on the impeller blades as well as an integrated gassing concept in an all-in-one device. The stirrer is fabricated by rapid prototyping and is equipped with a commercial micromesh membrane. Filtration performance is tested using a yeast cell suspension with different stirring speeds and aeration fluxes. We reduce membrane fouling by backflushing through the membrane with the product stream.
Asunto(s)
Reactores Biológicos , Biotecnología/instrumentación , Membranas Artificiales , Diseño de Equipo , Fermentación , Filtración/instrumentación , Presión , LevadurasRESUMEN
During this study the absorption rates of two contrast media were measured in double-blind design. 33 patients received lopamidol (Solutrast 300), and 30 patients Meglumine iothalamate (Conray 60). A regular absorption of the contrast media during ERC, ERP and ERCP could be stated. With reference to the absorption rates a slight, but for statistically not significant advantage for the contrast medium lopamidol could be ascertained. During ERC the absorption rates ranged from 0.4 to 30%, during ERP from 2.2 to 18.8% and during ERCP from 1.0 and 30.0%. Consequently the endoscopist always has to take into account an anaphylactoid reaction due to the systemic absorption of contrast media which, compared to other examinations with contrast media, happens relatively seldom.