COF-5/Pebax mixed-matrix membranes with enhanced CO2 removal ability for ECCO2R system

[Display omitted] Extracorporeal CO2 removal (ECCO2R) is a type of extracorporeal life support (ECLS) technology. It aims to remove carbon dioxide (CO2) from small flow of the blood and correct hypercapnia and related acidosis. The ECCO2R system removes CO2 retained in the patient’s body through the gas-blood exchange membranes, which in use, blood flows on the outside of the membrane, and the inside of the membrane is for gas flow. Existing ECCO2R system generally improves the emission rate of CO2 by the increase of the gas flow rate. However, there is a problem that O2 is simultaneously taken out, which will reduce the blood O2 concentration. Therefore, the gas-blood exchange membranes should not only increase the CO2 removal rate by the improvement of CO2/O2 selectivity, but also retain more O2 in the blood and then maintain the oxygen saturation of the blood. In present work, a method was proposed to fabricate COF-5/Pebax mixed matrix membranes (MMMs) on the PMP surface for enhancing CO2/O2 selectivity, which was increased from 0.96 to 5.57. The CO2 removal ability of COF-5/Pebax MMM was tested by blood circulation, and it was found that the CO2 removal effect was increased 10.9% than that of the pristine membranes. The O2 concentration was maintained at a higher level, about 1.69 times that of the pristine membranes. In contrast to the pristine PMP membrane, blood compatibility of COF-5/Pebax MMMs was improved because protein adhesion decreased by 44.75%. The results of cytotoxicity test and rabbit pyrogen test exhibited that the prepared COF-5/Pebax MMM presented great biosafety. Overall, the proposed COF-5/Pebax MMM has good performance in ECCO2R system and attractive potential for medical application.