화학공학소재연구정보센터
Journal of the American Chemical Society, Vol.141, No.32, 12697-12706, 2019
Helical Sulfono-gamma-AApeptides with Aggregation-Induced Emission and Circularly Polarized Luminescence
Aggregation-induced emission (AIE) was intensively studied because of packing of small molecules and polymers; however, mid-molecular-weight (1000-3000) molecular scaffold containing a precise number of AIE luminogens is rare. Herein, we report the investigation of three tetraphenylethylene (TPE)-modified sulfono-gamma-AApeptides in which multiple TPE moieties are conjugated to the chiral right-handed helical peptidomimetic backbone as functional side chains. The crystal structure of the TPE-alpha/sulfono-gamma-AA peptide 1 demonstrates that because of the rigid helical scaffold of the TPE-alpha/sulfono-gamma-AA peptides, the intramolecular rotations of the TPE with short linker are restricted, therefore leading to the boosted fluorescent emission in solution. Peptides 2 and 3 exhibit aggregation-induced emission enhancement (AIEE), possibly because of the combination of both AIE and rotation restriction. Moreover, because of their preoriented assembly induced by the right-handed helical scaffold, these emissive chiral luminogens show effective circularly polarized luminescence signals with high dissymmetry factor g(lum). Finally, the amphiphilic nature of TPE-alpha/sulfono-gamma-AA peptides could enable them to penetrate the bacterial membranes and exhibit strong fluorescence. Their antimicrobial activity and labeling-free character could further augment their potential applications in both materials and biomedical sciences.