A porphyrin derivative containing 2-(oxymethyl)pyridine units showing unexpected ratiometric fluorescent recognition of Zn2+ with high selectivity.
A porphyrin derivative (1), containing two 2-(oxymethyl)pyridine units has been designed and synthesized as chemosensor for recognition of metal ions. Unlike many common porphyrin derivatives that show response to different heavy metal ions, compound 1 exhibits unexpected ratiometric fluorescence response to Zn(2+) with high selectivity. The response of the novel chemosensor to zinc was based on the porphyrin metallation with cooperating effect of 2-(oxymethyl)pyridine units. The change of fluorescence of 1 was attributed to the formation of an inclusion complex between porphyrin ring and Zn(2+) by 1:1 complex ratio (K=1.04x10(5)), which has been utilized as the basis of the fabrication of the Zn(2+)-sensitive fluorescent chemosensor. The analytical performance characteristics of the proposed Zn(2+)-sensitive chemosensor were investigated. The sensor can be applied to the quantification of Zn(2+) with a linear range covering from 3.2x10(-7) to 1.8x10(-4) M and a detection limit of 5.5x10(-8) M. The experiment results show that the response behavior of 1 to Zn(2+) is pH-independent in medium condition (pH 4.0-8.0) and show excellent selectivity for Zn(2+) over transition metal cations.
Li
Chun-Yan
CY
State Key Laboratory of Chemo/Biosensing and Chemometrics, College of Chemistry & Chemical Engineering, Hunan University, Changsha 410082, PR China.
Zhang
Xiao-Bing
XB
Dong
Yan-Yan
YY
Ma
Qiu-Juan
QJ
Han
Zhi-Xiang
ZX
Zhao
Yan
Y
Shen
Guo-Li
GL
Yu
Ru-Qin
RQ
D005453:Fluorescence; D005456:Fluorescent Dyes / Q000138:chemical synthesis / Q000737:chemistry*; D006863:Hydrogen-Ion Concentration; D015394:Molecular Structure; D011166:Porphyrins / Q000138:chemical synthesis / Q000737:chemistry*; D011725:Pyridines / Q000737:chemistry*; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D013050:Spectrometry, Fluorescence / Q000295:instrumentation / Q000379:methods; D013056:Spectrophotometry, Ultraviolet / Q000295:instrumentation / Q000379:methods; D015032:Zinc / Q000032:analysis*
C530513:2-(oxymethyl)pyridine; D005456:Fluorescent Dyes; D011166:Porphyrins; D011725:Pyridines; D015032:Zinc