A smart NIR fluorescent probe for the highly selective detection of palladium

Abstract

A tailor-made colorimetric and NIR fluorescent probe for Pd⁰ was developed by introducing allyl chloroformate into the methylene blue (MB) fluorophore. The probe exhibited vivid color change and significant fluorescence enhancement towards Pd⁰, accompanied with excellent selectivity and sensitivity. No absorption and fluorescence response could be observed towards other metal ions. The fluorescence intensity of this probe showed a linear response to Pd⁰ in the concentration range of 0–2 μM with a detection limit of 5.7 nM. Moreover, living cell imaging results indicated that this probe holds promising application prospects for detecting intracellular Pd⁰ species based on its low cytotoxicity and specific turn-on NIR emission.