Enzyme-enhanced membranes for gas separation

Membranes are highly desirable for separating gases in life-support applications. They are small, light, efficient, selective and require little operational or physical maintenance. Facilitated transport membranes have particularly high flux and selectivity. We created enzyme-based facilitated transport membranes using isozymes and mutants as immobilized arrays alone and in conjunction with polymeric membranes. The enzyme operates efficiently at the low CO₂ concentrations encountered in respiratory gases and can bring CO₂ to near ambient levels. CO₂ flux is greatly enhanced and selectivities for CO₂ over O₂ of 200:1 or greater are possible. The enzymes are robust and stable for long periods under a variety of storage and use conditions.