Designing biomimetic membranes for ion transport

Supported Liquid Membrane Systems (SLMS) have previously been shown to be effective mimics of active transport of ions. This can be controlled through use of thin film, fixed site carrier membranes on the external surfaces of an SLMS, to encapsulate it. This film must exhibit selective facilitated transport characteristics. The authors demonstrate this entrapping concept here by incorporating their previously successful SLMS with a thin film coating of a cation exchange membrane, Nafion(R) 124. Successful experiments for nickel transport were conducted in a recirculating dialysis unit. The authors also attempted to use fixed site carrier membranes; an ethylene-acrylic acid ionomer. Preliminary data indicates the approach is be sound for some cations, however the data for nickel was not conclusive. The most probable design for biomedical applications appears to be a combination (laminate) system that incorporates supported liquid membranes and highly selective molecularly engineered thin film entrapping membranes utilizing advanced materials technologies