A Substitution‐Dependent Light‐Up Fluorescence Probe for Selectively Detecting Fe3+ Ions and Its Cell Imaging Application

• Published in: Advanced functional materials 2018-08, Vol.28 (35), p.n/a
• Main Authors: Feng, Xing, Li, Ying, He, Xuewen, Liu, Haixiang, Zhao, Zheng, Kwok, Ryan T. K., Elsegood, Mark R. J., Lam, Jacky W. Y., Tang, Ben Zhong
• Format: Article
• Language: English
• Subjects: acid dissociation constant; aggregation‐induced emission; cell imaging; Chemical properties; Emission; Ferric ions; Fluorescent indicators; Iron; iron (III); Materials science; molecular recognition; Organic chemistry; Position sensing; Substitutes
• ISSN: 1616-301X; 1616-3028
• DOI: 10.1002/adfm.201802833

Deliberate design of specific and sensitive molecular probes with distinctive physical/chemical properties for analyte sensing is of great significance. Herein, by taking advantage of the position‐dependent substituent effects, an aggregation‐induced emission featured iron (III) probe from ortho‐substituted pyridinyl‐functionalized tetraphenylethylene (TPE‐o‐Py) is synthesized. It displays high sensitivity and selectivity toward iron (III) detection. The recognition arises from the position isomer of ortho‐substitution, and the fact that TPE‐o‐Py has a low acid dissociation constant (pK a) that is close to that of hydrolyzed Fe3+. Importantly, TPE‐o‐Py as a light‐up fluorescence probe could be employed for Fe3+ sensing in living cells with a pronounced red‐shift in fluorescence emission. A aggregation‐induced emission featured Fe3+ probe from ortho‐substituted pyridinyl‐functionalized tetraphenylethylene (TPE‐o‐Py), which displays high sensitivity and selectivity toward Fe3+ detection both in solution and in living cells, is presented here. The molecular recognition mechanism arises from the position isomer of TPE‐o‐Py has low acid dissociation constant that is close to that of hydrolyzed Fe3+.