Novel engineered ion channel provides controllable ion permeability for polyelectrolyte microcapsules coated with a lipid membrane

The development of nanostructured microcapsules based on a biomimetic lipid bilayer membrane (BLM) coating of poly(sodium styrenesulfonate) (PSS)/poly(allylamine hydrochloride) (PAH) polyelectrolyte hollow microcapsules Is reported. A novel engineered ion channel, gramicidin (bis-gA), incorporated Into the lipid membrane coating provides a functional capability to control transport across the microcapsule wall. The microcapsules provide transport and permeation for drug-analog neutral species, as well as positively and negatively charged ionic species. This controlled transport can be tuned for selective release biomimetically by controlling the gating of incorporated bis-gA ion channels. This system provides a platform for the creation of "smart" biomimetic delivery vessels for the effective and selective therapeutic delivery and targeting of drugs.