Adhesive pi-clamping within synthetic multifunctional pores.

We report the design, synthesis, and evaluation of synthetic multifunctional pores with adhesive, that is, electron-deficient naphthalenediimide (NDI) pi-clamps at their inner surface. We find that, in lipid bilayer membranes, comparable synthetic pores with and without pi-clamps have similar, nanomolar activity. Functional relevance of adhesive pi-clamping within synthetic pores is demonstrated by means of an innovative in situ blocker screening method. The obtained line of experimental evidence includes (a) different blockage efficiency with and without pi-clamps (quantified as clamping factors), (b) increasing clamping factors with increasing blocker charge (supportive ion pairing), and, most importantly, (c) increasing clamping factors with increasing aromatic electron donor-acceptor interactions. The availability of advanced synthetic multifunctional pores with refined active sites is important for practical applications in domains such as drug discovery (enzyme inhibitor screening) and diagnostics (multianalyte sensing).