A novel "turn-on" fluorescent probe based on thiocarbamoyl-DHP for Hg2+ detection in water samples and living cells

Waroton Paisuwan; Tanapat Palaga; Thitiporn Pattarakankul; Vachiraporn Ajavakom; Mongkol Sukwattanasinitt; Mamoru Tobisu; Anawat Ajavakom

doi:10.1016/j.saa.2023.123783

A novel "turn-on" fluorescent probe based on thiocarbamoyl-DHP for Hg²⁺ detection in water samples and living cells

Spectrochim Acta A Mol Biomol Spectrosc. 2024 Mar 5:308:123783. doi: 10.1016/j.saa.2023.123783. Epub 2023 Dec 16.

Authors

Waroton Paisuwan¹, Tanapat Palaga², Thitiporn Pattarakankul², Vachiraporn Ajavakom³, Mongkol Sukwattanasinitt⁴, Mamoru Tobisu⁵, Anawat Ajavakom⁶

Affiliations

¹ Department of Chemistry, Faculty of Science, Chulalongkorn University, Pathumwan, Bangkok 10330, Thailand.
² Department of Microbiology, Faculty of Science, Chulalongkorn University, Pathumwan, Bangkok 10330, Thailand.
³ Department of Chemistry and Center of Excellence for Innovation in Chemistry, Faculty of Science, Ramkhamhaeng University, Bangkok 10240, Thailand.
⁴ Nanotec-CU Center of Excellence on Food and Agriculture, Department of Chemistry, Faculty of Science, Chulalongkorn University, Pathumwan, Bangkok 10330, Thailand.
⁵ Department of Applied Chemistry, Graduate School of Engineering, Osaka University, Suita, Osaka 565-0871; Innovative Catalysis Science Division, Institute for Open and Transdisciplinary Research Initiatives (ICS-OTRI), Osaka University, Suita, Osaka 565-0871, Japan.
⁶ Nanotec-CU Center of Excellence on Food and Agriculture, Department of Chemistry, Faculty of Science, Chulalongkorn University, Pathumwan, Bangkok 10330, Thailand. Electronic address: anawat.a@chula.ac.th.

PMID: 38134654
DOI: 10.1016/j.saa.2023.123783

Abstract

In this study, two fluorescent sensing probes, dihydropyridine (DHP) derivatives (DHP-CT1 and DHP-CT2) bearing phenoxy thiocarbonyl group, have been developed for Hg²⁺ detection. The tandem trimerization-cyclization of methylpropiolate with ammonium acetate gave 1.4-DHP and 1,2-DHP derivatives, which were reacted with O-phenylcarbonochloridothioate to produce DHP-CT1 and DHP-CT2, respectively. DHP-CT1 exhibits superior sensitivity and selectivity of fluorescence enhancement towards Hg²⁺ in aqueous media. The fluorescence intensity shows a good linear relationship with the concentration of Hg²⁺ in the range of 0-10 µM providing the extremely low LOD of 346 nM (69.4 ppb). The fluorescence enhancement is caused by the Hg²⁺ promoted hydrolysis of the thioamide bond releasing the fluorescent 1,4-DHP that was confirmed by NMR and HRMS. The quantitative analysis of Hg²⁺ in water samples using DHP-CT1 probe was demonstrated in aqueous solution and paper-based sensing strips. Furthermore, DHP-CT1 was also applied for monitoring intracellular Hg²⁺ in living RAW264.7 macrophages through fluorescence cell imaging.

Keywords: Dihydropyridine (DHP); Fluorescence enhancement; Fluorescent sensor; Hg(2+) detection; Thiocarbamate.

MeSH terms

Fluorescent Dyes* / chemistry
Magnetic Resonance Spectroscopy
Mercury* / analysis
Spectrometry, Fluorescence / methods
Water

Substances

Fluorescent Dyes
Water
Mercury