A BODIPY based emission signal turn-on probe toward multiple heavy metals

Abstract

A heavy metals sensor (2-N,N-bis(pyridin-2-ylmethyl)methanamine-BODIPY, DB) for the recognition of Pb²⁺, Ba²⁺, Cr²⁺, Cd²⁺, Hg²⁺, Sn²⁺, and Zn²⁺ was developed by anchoring (bis(pyridin-2-ylmethyl)amine) DPA unit to the BODIPY framework. It exhibited excellent sensitivity and selectivity against other competent metal ions. The stoichiometry of DB and metal ions were determined to be 1:1. The limit of detection of DB toward Pb²⁺, Ba²⁺, Cr²⁺, Cd²⁺, Hg²⁺, Sn²⁺, and Zn²⁺ was ranged from 60.07 to 89.37 nM. Photo induced transfer (PET) leads to the weak emission of BODIPY unit. When metal ions anchored with DPA, PET was blocked due to the weak electron donating ability of N in DPA to BODIPY and the highly emissive character of BODIPY was recovered, establishing a fluorescence switch.

Keywords:

• BODIPY
• fluorescence switch
• limit of detection
• PET
• sensitivity and selectivity

Additional information

Funding

This work was supported by the National Natural Science Foundation of China (grant no. 21772034) and the Program for Innovative Research Team in Science and Technology of Colleges and Universities in Henan Province (grant nos. 19IRTSTHN023 and 20IRTSTHN005). X. Li gratefully acknowledges the financial support of China Scholarship Council (CSC) for being a visiting scholar in Aoyama Gakuin University (grant no. 201908410053).