A highly selective fluorescent chemosensor for zinc ion and imaging application in living cells.
A new 2,6-bis(5,6-dihydrobenzo[4,5]imidazo[1,2-c]quinazolin-6-yl)-4-methylphenol (1) serves as a highly selective and sensitive fluorescent probe for Zn(2+) in a HEPES buffer (50 mM, DMSO:water = 1:9 (v/v), pH = 7.2) at 25 °C. The increase in fluorescence in the presence of Zn(2+) is accounted for by the formation of dinuclear Zn(2+) complex [Zn(2)(C(35)H(25)N(6)O)(OH)(NO(3))(2)(H(2)O)] (2), characterized by X-ray crystallography. The fluorescence quantum yield of the chemosensor 1 is only 0.019, and it increases more than 12-fold (0.237) in the presence of 2 equiv of the zinc ion. Interestingly, the introduction of other metal ions causes the fluorescence intensity to be either unchanged or weakened. By incubation of cultured living cells (A375 and HT-29) with the chemosensor 1, intracellular Zn(2+) concentrations could be monitored through selective fluorescence chemosensing.
Department of Chemistry, Burdwan University, Golapbug, Burdwan 713104, West Bengal, India.
Uday Chand
UC
Saha
Basab
B
Chattopadhyay
Koushik
K
Dhara
Sushil Kumar
SK
Mandal
Sandipan
S
Sarkar
Anisur Rahman
AR
Khuda-Bukhsh
Monika
M
Mukherjee
Madeleine
M
Helliwell
Pabitra
P
Chattopadhyay
D001562:Benzimidazoles / Q000138:chemical synthesis*; D002021:Buffers; D002413:Cations, Divalent; D045744:Cell Line, Tumor; D003408:Cresols / Q000138:chemical synthesis*; D018360:Crystallography, X-Ray; D005456:Fluorescent Dyes / Q000138:chemical synthesis*; D019073:HT29 Cells / Q000473:pathology / Q000648:ultrastructure; D006801:Humans; D006863:Hydrogen-Ion Concentration; D008545:Melanoma / Q000473:pathology / Q000648:ultrastructure; D011799:Quinazolines / Q000138:chemical synthesis*; D013050:Spectrometry, Fluorescence / Q000379:methods*; D015032:Zinc / Q000737:chemistry*
C558266:2,6-bis(5,6-dihydrobenzo(4,5)imidazo(1,2-c)quinazolin-6-yl)-4-methylphenol; D001562:Benzimidazoles; D002021:Buffers; D002413:Cations, Divalent; D003408:Cresols; D005456:Fluorescent Dyes; D011799:Quinazolines; D015032:Zinc