Reversible Cobalt Ion Binding to Imidazole-Modified Nanopipettes

摘要

In this report, we demonstrate that quartz nanopipettesnmodified with an imidazole-terminated silane respond tonmetal ions (Co2+) in solution. The response of nanopipettesnis evaluated through examination of the ionncurrent rectification ratio. When nanopipettes arencycled between solutions of different pH, adsorbednCo2+ can be released from the nanopipette surface, tonregenerate binding sites of the nanopipette. Thesenresults demonstrate that rectification-based sensingnstrategies for nanopore sensors can benefit from selectionnof recognition elements with intermediate bindingnaffinities, such that reversible responses can be attained.