摘要

In this study, tetraphenylthiophene (TP) with aggregation-induced emission enhancement (AIEE) property served as the terminal and central fluorophores of poly(gamma-benzyl-L-glutamate) (PBLG)-based polymers of TP1PBLG and TP2PBLG, respectively, to probe the relationship between the secondary structure (alpha-helix) of polypeptides and the AIEE-operative fluorescence (FL). Intermolecular aggregation of the central TP unit in the di-substituted TP2PBLG is sterically blocked by the large alpha-helical PBLG chains, which leads to the reduced AIEE-oriented FL. In contrast, the terminal TP units in TP1PBLG can easily approach each other to form aggregates with strong FL. Factors (e.g. solvent annealing) controlling the fraction of the alpha-helix chain also vary the corresponding emission intensity. The conformational difference between TP1PBLG and TP2PBLG evaluated from the infrared and the X-ray (wide-and small-angle) diffraction spectra is also used to verify its influence on the AIEE-operative FL behavior.