Fluorescent oligomer as a chemosensor for the label-free detection of Fe3+ and dopamine with selectivity and sensitivity

•A sensitive and selective turn-off fluorescence chemosensor, Tyloxapol, was developed.•Tyloxapol is one kind of water soluble fluorescent oligomer.•Tyloxapol can be used for the label-free detection of Fe3+ ions in aqueous solution.•Our strategy may offer a new approach for developing sensitive sensors in biological and environmental applications.

In this article, a sensitive and selective turn-off fluorescence chemosensor, Tyloxapol (one kind of water soluble oligomer), was developed for the label-free detection of Fe3+ ions in aqueous solution. Fluorescence (FL) experiments demonstrated that Tyloxapol was a sensitive and selective fluorescence sensor for the detection of Fe3+ directly in water over a wide range of metal cations including Na+, K+, Ag+, Hg2+, Cd2+, Co2+, Cu2+, Cr3+, Mn2+, Ba2+, Zn2+, Ni2+, Mg2+, Ca2+, and Pb2+. Moreover, the fluorescence intensity of Tyloxapol has shown a linear response to Fe3+ in the concentration range of 0–100 μmol L−1 with a detection limit of 2.2 μmol L−1 in aqueous solution. Next, based on a competition mechanism, another turn-on sensing application of the Tyloxapol/Fe3+ platform to probe dopamine (DA) against various other biological molecules such as other neurotransmitters or amino acids (norepinephrine bitartrate, acetylcholine chloride, alanine, valine, phenylalanine, tyrosine, leucine, glycine, histidine) were also investigated. It is expected that our strategy may offer a new approach for developing simple, cost-effective, rapid and sensitive sensors in biological and environmental applications.

Graphical abstractSchematic representation of fluorescent Tyloxapol for detection of Fe3+ ion and dopamine.Figure optionsDownload full-size imageDownload as PowerPoint slide