Chiral Selective Adhesion of Protein Droplets on Calix[4]arene-Enantiomer-Modified Surfaces

Chiral-specific assembly is involved in many biochemical processes, such as DNA hybridization, protein adhesion, and sugar recognition. However, the signals of chiral interaction are usually very weak, and it is difficult to investigate the enantioselective behaviors. Therefore, it is necessary to construct the functional materials to regulate the selective behaviors of protein droplets via weak chiral interaction, which is also significant for the biological process of protein adhesive behaviors and proteinic drug delivery. Here, S- and R-amino alcohol derivative of calix[4]arene enantiomers (R/S-AC4) were synthesized and modified onto Au-surfaces to fabricate the enantiomer's materials and investigate the chiral selective adhesion of protein droplets. Through the experiment of fluorescence titration and molecular docking simulation, bovine serum albumin (BSA) showed the stronger interaction with R-amino alcohol-calix[4]arene than S-amino alcohol-calix[4]arene on the molecular level. Notably, the sliding angle showed that the droplet of BSA selectively adhered to the R-amino alcohol-calix[4]arene-modified surface, while it released rapidly from S-amino alcohol-calix[4]arene-modified surface by virtue of chiral selectivity. This result not only provides an easy and convenient model to regulate the selective adhesion and release of protein from chemical view, but also realizes the signal transduction through the weak chiral interaction.