TY - JOUR
T1 - Fluorescence detection of lead(II) ions through their induced catalytic activity of DNAzymes
AU - Li, Chi Lin
AU - Liu, Kung Tien
AU - Lin, Yang Wei
AU - Chang, Huan Tsung
PY - 2011/1/1
Y1 - 2011/1/1
N2 - We have developed a fluorescence approach for the highly selective and sensitive detection of Pb2+ ions using AGRO100, a G-quadruplex DNAzyme. The sensing strategy is based on Pb2+ ions inducing increased DNAzyme activity of AGRO100 in the presence of hemin, which acts as a cofactor to catalyze H2O2-mediated oxidation of Amplex UltraRed (AUR). A test of eight aptamers of various sequences for the detection of Pb2+ ions revealed that AGRO100 performed the best in terms of sensitivity. The AGRO100-AUR probe exhibited high selectivity (>100-fold) toward Pb2+ ions over other tested metal ions. The fluorescence intensity (excitation/emission maxima, ca. 561/592 nm) of the AUR product was proportional to the concentration of Pb2+ ions over the range 0-1000 nM, with a linear correlation (R2 = 0.98). For 5 mM Tris-acetate (pH 7.4) solutions in the presence and absence of 100 mM NaCl, the AGRO100-AUR probe provided limits of detection (signal-to-noise ratio = 3) for Pb2+ ions of 1.0 and 0.4 nM, respectively. We validated the practicality of the use of the AGRO100-AUR probe for the determination of the concentrations of Pb 2+ ions in soil samples. This approach allows the determination of the concentrations of Pb2+ ions with simplicity, selectivity, and sensitivity.
AB - We have developed a fluorescence approach for the highly selective and sensitive detection of Pb2+ ions using AGRO100, a G-quadruplex DNAzyme. The sensing strategy is based on Pb2+ ions inducing increased DNAzyme activity of AGRO100 in the presence of hemin, which acts as a cofactor to catalyze H2O2-mediated oxidation of Amplex UltraRed (AUR). A test of eight aptamers of various sequences for the detection of Pb2+ ions revealed that AGRO100 performed the best in terms of sensitivity. The AGRO100-AUR probe exhibited high selectivity (>100-fold) toward Pb2+ ions over other tested metal ions. The fluorescence intensity (excitation/emission maxima, ca. 561/592 nm) of the AUR product was proportional to the concentration of Pb2+ ions over the range 0-1000 nM, with a linear correlation (R2 = 0.98). For 5 mM Tris-acetate (pH 7.4) solutions in the presence and absence of 100 mM NaCl, the AGRO100-AUR probe provided limits of detection (signal-to-noise ratio = 3) for Pb2+ ions of 1.0 and 0.4 nM, respectively. We validated the practicality of the use of the AGRO100-AUR probe for the determination of the concentrations of Pb 2+ ions in soil samples. This approach allows the determination of the concentrations of Pb2+ ions with simplicity, selectivity, and sensitivity.
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U2 - 10.1021/ac1028787
DO - 10.1021/ac1028787
M3 - Article
C2 - 21141923
AN - SCOPUS:78650767968
VL - 83
SP - 225
EP - 230
JO - Industrial And Engineering Chemistry Analytical Edition
JF - Industrial And Engineering Chemistry Analytical Edition
SN - 0003-2700
IS - 1
ER -