Bodipy-based chemosensors for highly sensitive and selective detection of Hg2+ ions

Abstract

Detection of heavy metals with high sensitivity and selectivity is of vital importance. In this study, we report the synthesis of small molecular chemosensors and the fabrication of corresponding macromolecular fluorescent chemosensors. Boron dipyrrole methane (BODIPY)-derived chemosensors, BE and BB, were designed and synthesized first. Then, they were incorporated into polymeric derivatives to prepare macromolecular fluorescent chemosensors. The small molecular sensors were highly sensitive and selective to Hg²⁺. Other ions and albumin did not exhibit clear interference to the sensing of Hg²⁺ ions. Once the macromolecular chemosensors were formed, the recognition ability was preserved; moreover, the sensitivity was even enhanced by the “molecular wire” mechanism. The minimum detection limits of four macromolecular chemosensors, PBEP, PBEB, PBBP and PBBB, for Hg²⁺ reached 2.05 μM, 0.23 μM, 4.23 μM, and 0.15 μM, respectively. Under natural light, the addition of Hg²⁺ led to significant color changes; also, they can be used as Hg²⁺-sensitive “naked eye” indicators in the natural environment.