Colorimetric and fluorimetric detection of Fe(III) using a novel chromenylium-cyanine near-infrared fluorescence probe: Photophysical properties, DFT studies and cell imaging

Pengwen Luo; Hong Chen; Xiaoxia Cheng; Lu Liu; Yihan Yang; Hengyu Wen; Bin Hu; Dan Zhou; Hualin Jiang

doi:10.1016/j.saa.2025.126593

Colorimetric and fluorimetric detection of Fe(III) using a novel chromenylium-cyanine near-infrared fluorescence probe: Photophysical properties, DFT studies and cell imaging

Spectrochim Acta A Mol Biomol Spectrosc. 2025 Jun 20:343:126593. doi: 10.1016/j.saa.2025.126593. Online ahead of print.

Authors

Pengwen Luo¹, Hong Chen¹, Xiaoxia Cheng¹, Lu Liu¹, Yihan Yang¹, Hengyu Wen¹, Bin Hu², Dan Zhou³, Hualin Jiang⁴

Affiliations

¹ Key Laboratory of Jiangxi Province for Persistent Pollutants, Control and Resources Recycle, Nanchang Hangkong University, 696 Fenghe South Avenue, Nanchang 330063, China.
² Key Laboratory of Jiangxi Province for Persistent Pollutants, Control and Resources Recycle, Nanchang Hangkong University, 696 Fenghe South Avenue, Nanchang 330063, China. Electronic address: bhunchu@163.com.
³ Key Laboratory of Jiangxi Province for Persistent Pollutants, Control and Resources Recycle, Nanchang Hangkong University, 696 Fenghe South Avenue, Nanchang 330063, China. Electronic address: zhoudan@nchu.edu.cn.
⁴ Key Laboratory of Jiangxi Province for Persistent Pollutants, Control and Resources Recycle, Nanchang Hangkong University, 696 Fenghe South Avenue, Nanchang 330063, China. Electronic address: hua20022000@126.com.

PMID: 40580674
DOI: 10.1016/j.saa.2025.126593

Abstract

A novel chromenylium-cyanine near-infrared fluorescent probe named FTP is devised and successfully fabricated by using a Rhodamine derivative as the fluorescence-generating precursor for selectively and sensitively detecting Fe³⁺ in aqueous environments. Notably, its maximum emission wavelength reaches up to 743 nm, which lies in the first near-infrared window. The structure of FTP underwent characterization via Fourier Transform Infrared Spectroscopy (FTIR), Liquid Chromatography-Mass Spectrometry (LC-MS) and Nuclear Magnetic Resonance (NMR). The probe FTP demonstrates excellent selectivity and sensitivity toward Fe³⁺, achieving low detection limits of 79.7 nM (Ultraviolet-visible detection) and 24.0 nM (Fluorescence detection), as well as distinct colorimetric changes and an "off-on" fluorescence response. The 1:1 coordination mechanism between FTP and Fe³⁺ was further validated through LC-MS, ¹H NMR, calculations based on Density Functional Theory (DFT), and an analysis of Job's plot. Notably, FTP exhibits excellent biocompatibility and was successfully applied to fluorescence imaging in MCF-7 and HepG2 cells as well as in living mice, highlighting its potential for disease diagnosis and therapeutic monitoring.

Keywords: Cell imaging; Chromenylium-cyanine; Fe(3+) sensor; Fluorescence probe; Near-infrared.