TY - JOUR
T1 - Spiropyran-based fluorescent anion probe and its application for urinary pyrophosphate detection
AU - Shao, Na
AU - Wang, Hao
AU - Gao, Xiadi
AU - Yang, Ronghua
AU - CHAN, Wing Hong
N1 - The work was supported by the National Natural Foundation of China (20775005 and 20905008), the National Grand Program on Key Infectious Disease (2009ZX10004-312), and the Hong Kong Research Grant Council (HKBU 200407).
PY - 2010/6/1
Y1 - 2010/6/1
N2 - In recent decades, numerous spiropyran derivatives have been designed and utilized for optical sensing of metal ions. However, there is still less research on spiropyran-based anion sensors. In this work, a new spiropyran compound (L) appended with a pendant bis(2-pyridylmethyl)amine was synthesized and used in fluorescent sensing of pyrophosphate ion (PPi) in aqueous solution. The molecular recognition and signal transduction are based on the cooperative ligation interactions and the ligation-induced structural conversion of the spiropyran, which leads to a significant change in the photophysical property of the spiropyran. In an ethanol/water solution (30:70, v/v) at pH 7.4, ligation of L with Zn2+ causes an intense fluorescence emission at 620 nm at the expense of the original fluorescence at 560 nm. Once PP i was introduced, interaction between PPi and the L-Zn2+ complex leads to full quenching of the 620 nm band emission which was concomitant with recovery of the 560 nm band emission, and the fluorescence intensity ratio, F560/F620, is proportional to the PPi concentration. Under the optimum condition, the L-Zn 2+ complex responds to PPi over a dynamic range of 1.0 × 10-6 to 5.0 × 10-4 M, with a detection limit of 4.0 × 10-7 M. The fluorescence response is highly selective for PPi over other biologically related substrates, especially the structurally similar anions, such as phosphate and adenosine triphosphate. The mechanism of interaction among L, Zn2+, and PPi was primarily studied by 1H NMR, 31P NMR, and HRMS. To demonstrate the analytical application of this approach, the PPi concentration in human urine was determined. It was on the order of 3.18 × 10-5 M, and the mean value for urinary PPi excretion by three healthy subjects was 62.4 μmol/24 h.
AB - In recent decades, numerous spiropyran derivatives have been designed and utilized for optical sensing of metal ions. However, there is still less research on spiropyran-based anion sensors. In this work, a new spiropyran compound (L) appended with a pendant bis(2-pyridylmethyl)amine was synthesized and used in fluorescent sensing of pyrophosphate ion (PPi) in aqueous solution. The molecular recognition and signal transduction are based on the cooperative ligation interactions and the ligation-induced structural conversion of the spiropyran, which leads to a significant change in the photophysical property of the spiropyran. In an ethanol/water solution (30:70, v/v) at pH 7.4, ligation of L with Zn2+ causes an intense fluorescence emission at 620 nm at the expense of the original fluorescence at 560 nm. Once PP i was introduced, interaction between PPi and the L-Zn2+ complex leads to full quenching of the 620 nm band emission which was concomitant with recovery of the 560 nm band emission, and the fluorescence intensity ratio, F560/F620, is proportional to the PPi concentration. Under the optimum condition, the L-Zn 2+ complex responds to PPi over a dynamic range of 1.0 × 10-6 to 5.0 × 10-4 M, with a detection limit of 4.0 × 10-7 M. The fluorescence response is highly selective for PPi over other biologically related substrates, especially the structurally similar anions, such as phosphate and adenosine triphosphate. The mechanism of interaction among L, Zn2+, and PPi was primarily studied by 1H NMR, 31P NMR, and HRMS. To demonstrate the analytical application of this approach, the PPi concentration in human urine was determined. It was on the order of 3.18 × 10-5 M, and the mean value for urinary PPi excretion by three healthy subjects was 62.4 μmol/24 h.
UR - http://www.scopus.com/inward/record.url?scp=77952983932&partnerID=8YFLogxK
U2 - 10.1021/ac1008089
DO - 10.1021/ac1008089
M3 - Journal article
C2 - 20459115
AN - SCOPUS:77952983932
SN - 0003-2700
VL - 82
SP - 4628
EP - 4636
JO - Analytical Chemistry
JF - Analytical Chemistry
IS - 11
ER -