Ultra-trace level detection of Cu2+ in an aqueous medium by novel Zn(ii)-dicarboxylato–pyridyl coordination polymers and cell imaging with HepG2 cells

Fluorescent 1D Zn(ii) coordination polymers are aggregated via noncovalent interactions. The emission of the CPs is exclusively quenched by Cu²⁺ and the LOD is at μM range. In aqueous medium internalization CPs within HepG2 cells is detected by microscopic cell image using Cu²⁺.

Novel rhodamine-based colorimetric and fluorescent sensor for the dual-channel detection of Cu2+ and Co2+/trivalent metal ions and its AIRE activities

A rhodamine hydrazone 1 bearing coumarin moiety was designed and prepared. Compound 1 exhibited high selectivity toward Co²⁺ and trivalent metal ions with fluorescence enhancement in CH₃OH solution. However, 1 selectively responded to Al³⁺ in nearly pure H₂O media and was further applied to monitor Al³⁺ in live cells. Moreover, 1 could also act as a colorimetric probe toward Cu²⁺ in either CH₃OH or H₂O solution. In addition, sensor 1 displayed aggregation-induced ratiometric emission (AIRE) activities in mixed H₂O/CH₃OH solution.

Ratiometric fluorescent probe based on pyrrole-modified rhodamine 6G hydrazone for the imaging of Cu2+ in lysosomes

A novel rhodamine-based Schiff base derivative was obtained via the simple condensation of substituted formyl-1H-pyrrole and rhodamine 6G hydrazone. Fluorescence resonance energy transfer enabled the subsequent use of the derivative as a naked-eye colorimetric and ratiometric fluorescent sensor for Cu²⁺ in semi-aqueous solution, and the existence of the morpholine group enabled the further application of the sensor in imaging Cu²⁺ in the lysosomes of HeLa cells.

Selective recognition of Cu (II) and Fe (III) using a pyrene based chemosensor

A pyrene-based colorimetric chemosensor 1-(pyren-1-yl)-N,N-bis-(pyridine-2-ylmethyl)methanamine (1) was synthesised for selective detection of Cu (II) and Fe (III) over the other metal cations Ni²⁺, Mg²⁺, Cd²⁺, Hg²⁺, Na⁺, K⁺, Ca²⁺, Co²⁺, Cr³⁺, Pb²⁺ and Zn²⁺. The significant changes in UV-vis absorption band of receptor 1 and the emergence of 660nm band in presence of Cu²⁺ ion indicates the selective binding of Cu²⁺ ion as compared to other metal cations which could easily be identified from the naked eye strong colour change. Job plots suggest a 1:1 and 2:1 stoichiometric binding of Cu²⁺ and Fe³⁺, respectively, which was evidenced by ESI-MS analysis. Chemosensor 1 explores a cost-effective and selective colorimetric sensor for naked eye detection of trace amount of Cu²⁺ and Fe³⁺ ions in presence of other metal cations.