A novel recyclable magnetic nanostructure for highly sensitive, selective and reversible detection of zinc ions in aqueous solutions

Abstract

The synthesis and characterisation of a novel dansylated magnetic nanostructure, namely Fe3O4@SiO2-PEG-DnS, is reported here. Investigations of its fluorescent properties showed that the presence of the PEG moiety significantly enhanced the fluorescent intensity of the nanostructure when compared to both the free dansyl fluorophore and a nanostructure that contained no PEG spacer between the core and the attached dansyl group. The addition of zinc (Zn 2+) ions to the aqueous suspension of Fe3O4@SiO2-PEG-DnS led to a 12.5-fold decrease in intensity. The quenching was selective to only Zn 2+. No interference was observed by other examined metal cations, including cadmium (Cd 2+). A very low detection limit of 6.00 nM in relation to zinc ions was demonstrated. In addition, the newly developed magnetic nanostructured chemosensor was found to be highly stable, reusable and recoverable.

White-light-emitting Ln-hydrogels with multi-stimuli responsiveness and applications in environmental sensing and anti-counterfeiting

“…The other reason for selective fluorescence quenching caused by Cu 2+ may be due to the paramagnetic effect from the spin-orbit coupling of Cu 2+ . 46 As shown in Fig. S18 (ESI †), the EPR signal of MPF-Eu/Tb was silent, and the presence of various metal ions did not affect it except for Cu 2+ .…”

An Adenine‐Based Chromone‐Coupled ‘Off‐On‐Off’ Fluorogenic Dyad for Cascade Detection of Zn2+ and HSO₄− Ions or Zn2+ Ions and Picric Acid

“…[35][36][37][38][39][40][41][42][43] Furthermore, Hg 2 + and Cd 2 + metal ions have shown some common chemical and physical characteristics; because of this, it is tough and challenging to detect Zn 2 + ions in their presence. [44][45][46][47] Therefore, the development of luminescent chemosensors is considered essential to distinguish between Zn 2 + ions under colonial ionic crowding environments when Hg 2 + and Cd 2 + are present at the same time. [48][49][50][51][52][53] The resulting metal ion chelated chemosensor could function as a crucial photonic device for identifying many target analytes if the chemosensor exhibits momentous fluorescence enhancement as a result of the binding with Zn 2 + ions.…”

“…Additionally, fluorescent chemosensors have real‐time detection capabilities because they can be used for both intercellular and on‐site detection [35–43] . Furthermore, Hg 2+ and Cd 2+ metal ions have shown some common chemical and physical characteristics; because of this, it is tough and challenging to detect Zn 2+ ions in their presence [44–47] . Therefore, the development of luminescent chemosensors is considered essential to distinguish between Zn 2+ ions under colonial ionic crowding environments when Hg 2+ and Cd 2+ are present at the same time [48–53] …”

Desenvolvimento de um nanosensor fluorescente baseado em nanopartículas magnéticas com estrutura caroço-casca

“…Outro sensor químico fluorescente e colorimétrico para íons mercúrio (II) baseado em nanopartículas de Fe3O4@SiO2 funcionalizadas com N-(rodamina-6G) lactama-etilenodiamina foi desenvolvido, em que a sua seletividade foi melhor do que a seletividade do fluoróforo isolado sob as mesmas condições [98] . Apesar de muitos estudos focarem na detecção dos íons Hg 2+ [99,100] , os processos de modificação e de funcionalização dos compostos fluorescentes e das nanopartículas, respectivamente, têm contribuído para o desenvolvimento de sensores capazes de realizar a determinação de outros íons como Zn 2+ [101,102] , Cu 2+ [103 -105] , Ni 2+ [106] e Fe 3+ [107] .…”