A fluorescent sensor for Cu²⁺and Fe³⁺based on multiple mechanisms

Abstract

A new fluorescent sensor for selective and sensitive sensing of Cu 2+ and Fe 3+ based on the rational control of multiple mechanisms has been developed. Sensor L, is weak-fluorescent (ϕ=0.029) due to the C=N isomerization and PET process. Upon binding with Cu 2+ , the complex L+Cu 2+ can give a rematkable fluorescence enhancement (ϕ=0.182) with a limit of detection down to 1.3×10 -8 mol/L because of the both inhibition of C=N isomerization and PET process. However, upon binding with Fe 3+ , the original weak fluorescence of L is completely quenched (ϕ=0.002) due to the paramagnetic quenching property. In addition, the lighted complex L+Cu 2+ could be further used as a new platform for ultrasensitive detection of Fe 3+ based on the fluorescence "turn-off" response with a limit of detection down to 2.4×10 -8 mol/L in aqueous solution.

On/Off Fluorescent Chemosensor for Selective Detection of Divalent Iron and Copper Ions: Molecular Logic Operation and Protein Binding

“…The nonbonding electron pair of nitrogen atom transferred to naphthyl ring results in weak fluorescence emission for LH due to photoinduced electron transfer (PET) process. 25,26…”

A new fluorescent and colorimetric chemosensor for Al3+ and F−/CN− based on a julolidine unit and its bioimaging in living cells

“…In addition, the isomerization of the C]N bond was suppressed, which stabilized the chelate complexation of HL with Al 3+ and increased the rigidity of the molecule, thereby causing a chelation-enhanced uorescence (CHEF) effect. [50][51][52] (Scheme 1).…”

A tricorn‐rhodamine fluorescent chemosensor for detection of Co2+ ions

“…Compound 1 was collected as a pink powder (yield 7.06 g, 82%). 1 H NMR (DMSO-d 6 , 300 MHz) δ: 1.2 (t, 6H, CH 3 ), 1.87 (s, 6H, ArCH 3 ), 3.08-3.17 (m, 4H, ArNHCH 2 ), 4.22 (s, 2H, NH 2 ), 5.00 (t, 2H, ArNH), 6.09 (s, 2H, ArH), 6.26 (s, 2H, ArH), 6.91-6.94 (m, 1H, ArH), 7.44-7.47 (m, 2H, ArH), 7.74-7.77 (m, 1H, ArH) ( Figure S1).…”

“…The recognition and detection of physiologically and environmentally significant metal ions, especially toxic heavy metal ions, have arisen as a momentous goal in the field of chemical sensors at this time . Among numerous detection methods, fluorimetric methods are widely used due to their high sensitivity, high speed responsibility, lower sample consumption, wide linear range and simplicity of operation.…”