Researchers from the Adolphe Merkle Institute (AMI; Fribourg, Switzerland; www.ami.swiss), together with international collaborators, have pioneered a novel method for creating thin, energy-converting membranes that mimic the structure and function of biological cell membranes. This discovery, described in a recent issue of Nature, could have significant applications in fields ranging from implantable artificial electric organs to water desalination.
The new technique leverages the interface of an aqueous two-phase system to form and stabilize these membranes. By carefully controlling the conditions under which two immiscible water-based solutions interact with the opposing sides of these membranes, the researchers created defect-free membranes that are just 35 nm thick and can cover areas larger than 10 cm2.
The method employs block copolymers (BCPs), highly tunable polymers consisting of two or more distinct polymer segments, to form a bilayer at the interface of the two phases. The resulting membranes exhibit remarkable mechanical properties and self-healing capabilities, making them robust and durable for practical use.
In this project, membrane ion-transport functionality was inspired by the types of rays and fish that can produce electrical signals in their bodies
These artificial membranes replicate the selective ion-transport functions of natural cell membranes. By incorporating a natural transport peptide, the membranes achieve high ion selectivity, allowing them to generate electric power from solutions of different salts. This functionality is inspired by the electric organs of rays and other electric fish, which use similar principles to generate power. Potential applications include energy storage, water desalination, medical treatment (dialysis) and even implantable electric-power sources.