Adaptive insertion of the hydrophobic anchor into poly(ethylene glycol) host for programmable surface functionalization

Abstract

Covalent and non-covalent molecular binding represent two strategies to tailor surface properties and functions. However, the lack of responsiveness or the requirement of specific binding groups challenged the spatial-temporal control of surface functionalization. Here, we report the adaptive insertion of the hydrophobic anchor into poly(ethylene glycol) (PEG) host as a new non-covalent binding strategy for surface functionalization. By using polycyclic aromatic hydrocarbons as the hydrophobic anchor, hydrophilic charged and non-charged functional modules were spontaneously loaded onto the polymeric membrane in 2 minutes without the assistance of any catalysts and binding groups. The thermodynamically favorable insertion of hydrophobic anchors can be reversed by pulling the functional modules, enabling the programmable surface functionalization. We anticipate that the adaptive molecular recognition between hydrophobic anchor and PEG will challenge the hydrophilic understanding of PEG and enhance the progress in nanomedicine, advanced materials, and nanotechnology.