Chirality Triggered Wettability Switching on Smart Polymer Surface
Guangyan Qing and Taolei Sun*
Adv. Mater. 2011, 23, 1615–1620
DOI: 10.1002/adma.201004082
Chiral recognition and enantioselective interaction for biomolecules are of fundamental importance in biological processes in nature, and also for various applications in biochemistry, medicine, and industry. For different chiral molecular species, a lot of synthetic chiral recognition systems have been developed, with purposes of chiral detection and separation, and asymmetric catalysis, etc. However, recognition is usually only the first step, and a more appealing task is to translate the chiral signals into other processes or macroscopic properties and functions of materials, which will bring great advantages to applications, but is quite challenging for chemists. Here we report the chirality triggered wettability switching on smart copolymer films containing dipeptide units. Monosaccharide enantiomers stereoselectively interact with L-dipeptide units, which is translated into differential conformational changes of copolymer chains via the cooperative hydrogen bonding interaction. It results in discrepant wettability responses with contact angle difference larger than 90o on a textured substrate, being accompanied by changes of other film properties, e.g. volume. This work points a promising direction for developing novel chirality-responsive materials, which find broad applications in controllable chiral separation, chiral medicine, smart bio-devices, etc.
