Ion-Driven ATP Pump by Self-Organized Hybrid Membrane Materials

Abstract
We report new hybrid organic−inorganic materials, based on macrocyclic receptors 1−3 self-organized in tubular superstructures prepared by sol−gel process. Fourier transform infrared (FTIR) and NMR spectroscopic analyses demonstrate that the self-organization by hydrogen bonding of organogel superstructures of 2 and 3 were preserved in the hybrid materials throughout the sol−gel process. The molecular arrangement of heteroditopic receptors defines a particularly attractive functional transport device for both cation (tubular macrocycles) and anion (sandwich-urea) directional-diffusion transport mechanism in the hybrid membrane material. This system has been employed successfully to design a solid dense membrane, functioning as an ion-powered adenosine triphosphate (ATP2-) pump, and illustrates how a self-organized hybrid material performs interesting and potentially useful functions.