Single-molecule force spectroscopy quantification of adhesive forces in cucurbit[8]uril host-guest ternary complexes.

Abstract

Cucurbit[8]uril (CB[8]) heteroternary complexes display certain characteristics making them well-suited for molecular level adhesives. In particular, the ability to control adhesion through careful choice of host-guest binding pairs enables specific, fully reversible adhesion. Understanding the effect of the environment on the adhesive system is also critical when developing new molecular level adhesives. Here we explore the binding forces involved in the methyl viologen · CB[8] · napthol heteroternary complex using single-molecule force spectroscopy (SMFS) under a variety of conditions. From SMFS, the interaction of a single ternary complex was found to be in the region of 140 pN. Additionally, a number of surface interactions could be readily differentiated using the SMFS technique allowing for a deeper understanding of the dynamic heteroternary CB[8] system on the single-molecule scale.