A long-wavelength tetraphenylethylene-derived fluorescent probe for sensitive detection of heparin and protamine
摘要
Heparin and protamine are vital biomacromolecules extensively used in clinical settings, necessitating precise monitoring of their concentrations. In this study, a novel positively charged fluorescent probe was developed, derived from an aggregation-induced emission (AIE) luminogen, tetraphenylethylene (TPE), for the detection of heparin and protamine. The probe was designed by modifying TPE with a 4-methyl-1-(3-(trimethylammonio)propyl)pyridin-1-ium bromide moiety, which imparts enhanced water solubility and long-wavelength emission. The probe (TPE-PY-N) binds electrostatically to heparin, inducing a significant “turn-on” fluorescence response. It exhibits high selectivity and sensitivity, with a limit of detection (LOD) of 10.7 ng/mL for heparin in buffer solution. Subsequently, the addition of protamine displaces the probe molecules, leading to a “turn-off” emission. The probe’s high selectivity and sensitivity position it as a promising tool for sensing heparin and protamine in buffer and highly diluted serum.