Naked eye sensing of toxic metal ions in aqueous medium using thiophene-based ligands and its application in living cells.
Thiophene-based diimine (R1) and monoimine (R2) were synthesized in a single step, and their cation binding affinity was tested using colorimetric and UV-vis spectral studies. R1 selectively shows a colorimetric turn-on response for Pb(2+), Hg(2+) ions and colorimetric turn-off with Sn(2+) ions, and R2 shows visual response for Cu(2+) and Hg(2+) over other examined metal ions in aqueous medium. R1 forms 1:1 complex with Pb(2+), Hg(2+), and Sn(2+) and exhibits fluorescence quenching, whereas R2 shows 2:1 complex with Hg(2+), Cu(2+) and shows fluorescence enhancement. The structural and electronic properties of the sensors and their metal complexes were also investigated using Density Functional Theory calculations. R2 was also successfully demonstrated as a fluorescent probe for detecting Cu(2+) ions in living cells.
Organic and Polymer Synthesis laboratory, Department of Chemistry, National Institute of Technology, Tiruchirappalli, 620 015, India.
Duraisamy
D
Udhayakumari
Sivalingam
S
Suganya
Sivan
S
Velmathi
Davoodbasha
D
MubarakAli
D002413:Cations, Divalent; D003124:Colorimetry / Q000379:methods*; D003300:Copper / Q000032:analysis; D007854:Lead / Q000032:analysis; D057230:Limit of Detection; D008628:Mercury / Q000032:analysis; D019216:Metals, Heavy / Q000032:analysis*; D011789:Quantum Theory; D062165:Receptors, Artificial / Q000138:chemical synthesis / Q000737:chemistry*; D012996:Solutions; D013050:Spectrometry, Fluorescence; D013056:Spectrophotometry, Ultraviolet; D013876:Thiophenes / Q000138:chemical synthesis / Q000737:chemistry*; D014001:Tin / Q000032:analysis; D014867:Water / Q000737:chemistry; D014874:Water Pollutants, Chemical / Q000032:analysis*
D002413:Cations, Divalent; D019216:Metals, Heavy; D062165:Receptors, Artificial; D012996:Solutions; D013876:Thiophenes; D014874:Water Pollutants, Chemical; D014867:Water; D007854:Lead; D014001:Tin; D003300:Copper; D008628:Mercury
DFT; aqueous medium; cation recognition; chromogenic sensor; living cells; schiff base