Amphiphilic oligoamides as versatile, acid-responsive gelators

Abstract

Six oligoamides with the same backbone but different side and end chains, G1–G6, were designed and synthesized. Screening the gelating abilities of these oligoamides revealed G2 as a versatile gelator capable of forming stable hydrogels as well as several organogels. From UV, fluorescence, NMR, and SEM studies, the formation of hydrogels is driven by hydrophobic forces and π–π stacking while the gelation of nonpolar organic solvents relies on hydrogen-bonding interactions. The hydrogel of G2 is able to encapsulate and release medicinally important polar substances into water with acid-responsiveness.