Ethyl-substituted Thioflavin T as a Fluorescent Probe for Detecting the Conformation of Transferrin

Human serum transferrin (hTf) is found that can be used as novel drug active targeted vector, which have broad application prospects in the field of tumor-targeted therapeutics. A new method to recognize human transferrin (hTf) conformations was developed using ThT-E. ThT-E with three ethyl functional groups has better hydrophobicity than ThT, which can better recognize transferrin and achieve detection of the open conformation of Tf (apo-Tf) against the closed one (holo-Tf). In this study, ThT-E and ThT with similar main core structures were selected to evaluate the effect of heterocycles on hTf binding by spectroscopic methods, and a more excellent fluorescent probe ThT-E was selected for the recognition of transferrin conformation. And ThT-E has a detection limit of 0.27 mu M for apo-Tf. This study provides a theoretical basis for ThT-E as a biomolecular probe for detecting the mutual conversion of two conformational proteins.