A rhodamine‐triazole fluorescent chemodosimeter for Cu²⁺ detection and its application in bioimaging

Abstract

A rhodamine-based fluorescent chemodosimeter rhodamine hydrazide-triazole (RHT) tethered with a triazole moiety was developed for Cu 2+ detection. In aqueous medium, the RHT probe exhibited high selectivity and sensitivity toward Cu 2+ among other metal ions. The addition of Cu 2+ triggered a fluorescence emission of RHT by 384-fold (Φ = 0.33) based on a ring-opening process and a subsequent hydrolysis reaction. Moreover, RHT also showed a selective colorimetric response toward Cu 2+ from colorless solution to pink, readily observed with the naked eye.The limit of detection of RHT for Cu 2+ was calculated to be 1 nM (0.06 ppb). RHT was successfully demonstrated to detect Cu 2+ in Chang liver cells by confocal fluorescence microscopy.

Rhodamine-Triazole Functionalized Fe3O4@SiO2 Nanoparticles as Fluorescent Sensors for Heavy Metal Ions

“…The mass spectrum of the RBT- ). This outcome is consistent with rhodamine ring-opening followed by hydrolysis as postulated previously 27 .…”

“…Rhodamine-N-propargyl alkyne was prepared according to a previously reported procedure 27 . The crude product was purified by silica column chromatography with 1% (v/v) CH 3 OH/CH 2 Cl 2 system as a mobile phase to obtain a light brown solid in 75% yield.…”

“…nanopar ticles were synthesized by the click chemistry protocol (copper(I)-catalyzed azide alkyne cycloaddition, CuAAC) which involved grafting rhodamine-N-propargyl alkyne moieties on the surface of Fe 3 O 4 @SiO 2 nanoparticles 27 . Rhodamine-N-propargyl alkyne was synthesized in good yield from the condensation of rhodamine B with hydrazine to obtain rhodamine hydrazide, followed by nucleophilic substitution with electrophilic propargyl bromide, as shown in Scheme 1.…”

A new benzimidazole‐based selective and sensitive ‘on–off’ fluorescence chemosensor for Cu2+ ions and application in cellular bioimaging

“…In recent years, the design and preparation of fluorescent chemosensors to recognize and detect metal ions has attracted increasing interest due to their high selectivity and sensitivity, on‐site monitoring, fast response and lower cost . So far, many Cu 2+ fluorescent chemosensors based on different kinds of materials have been reported …”

Recent progress in the development of fluorescent probes for hydrazine

“…Alternatively, analytical techniques based on fluorescence sensor systems are very popular because fluorescence measurements are usually easy to perform, inexpensive, very sensitive (parts per billion/trillion) with detection limits as low as sub‐parts‐per million, and able to be employed for in situ and in vivo monitoring . Hydrazine can act as a good nucleophile for a variety of transformations in synthetic chemistry, such as hydrazone formation, Wolff–Kishner reduction, heterocyclic chemistry, deprotection of phthalimides and so on.…”