1.D.55 The Porphyrin-based Nanopore (PorNP) Family
A porphyrin-based nanopore has been constructed through a bilayer lipid membrane (BLM) (Satake et al. 2008). The macrocyclic porphyrin (inner diameter = ca. 2.1 nm), having six carboxylic acid groups directed up and down, was synthesized by self-assembly of three trisporphyrins, metathesis linking, and subsequent hydrolysis. The porphyrin was incorporated into a soybean lecithin based BLM, and the ion currents through the nanopore were observed under 500 mM KCl, LiCl, CaCl2, and tetraalkylammonium chloride solutions, indicating formation of a large pore through BLM. Blocking of the ion current was achieved by addition of the polycationic fourth-generation PAMAM dendrimer (Satake et al. 2008).