title: A new rhodamine-based fluorescent chemodosimeter for mercuric ions in water media.
abstract: A new rhodamine-ethylenediamine-nitrothiourea conjugate (RT) was synthesized and its sensing property as a fluorescent chemodosimeter toward metal ions was explored in water media. Analytical results from absorption and fluorescence spectra revealed that the addition of Hg(2+) ions to the aqueous solution of the chemodosimeter RT caused a distinct fluorescence OFF-ON response with a remarkable visual color change from colorless to pink; however, no clear spectral and color changes were observed from other metal ions including: Zn(2+) , Cu(2+) , Cd(2+) , Pb(2+) , Ag(+) , Fe(2+) , Cr(3+) , Co(3+) , Ni(2+) , Ca(2+) , Mg(2+) , K(+) and Na(+) . The sensing results and the molecular structure suggested that a Hg(2+) -induced a desulfurization reaction and cyclic guanylation of the thiourea moiety followed by ring-opening of the rhodamine spirolactam in RT are responsible for a distinct fluorescence turn-on signal, indicating that RT is a remarkably sensitive and selective chemodosimeter for Hg(2+) ions in aqueous solution. Hg(2+) within a concentration range from 0.1 to 25 μM can be determined using RT as a chemodosimeter and a detection limit of 0.04 μM is achieved.
authors: Hue University, Hue City, 8454, Vietnam.
authors: Phan Tu
authors: PT
authors: Quy
authors: Nguyen Khoa
authors: NK
authors: Hien
authors: Nguyen Chi
authors: NC
authors: Bao
authors: Doan Thanh
authors: DT
authors: Nhan
authors: Dang Van
authors: DV
authors: Khanh
authors: Nguyen Thi Ai
authors: NT
authors: Nhung
authors: Truong Quy
authors: TQ
authors: Tung
authors: Nguyen Dinh
authors: ND
authors: Luyen
authors: Duong Tuan
authors: DT
authors: Quang
mesh_terms: D005029:Ethylenediamines / Q000737:chemistry; D005456:Fluorescent Dyes / Q000138:chemical synthesis / Q000737:chemistry*; D057230:Limit of Detection; D008628:Mercury / Q000032:analysis*; D008670:Metals / Q000737:chemistry; D012235:Rhodamines / Q000737:chemistry*; D013050:Spectrometry, Fluorescence; D013056:Spectrophotometry, Ultraviolet; D013890:Thiourea / Q000737:chemistry
chemical_list: D005029:Ethylenediamines; D005456:Fluorescent Dyes; D008670:Metals; D012235:Rhodamines; C031234:ethylenediamine; D008628:Mercury; D013890:Thiourea
keywords: Hg2+ detection; chemodosimeter; fluorescence OFF-ON; rhodamine derivative