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Colorimetric Detection of ATP by a Chlorophosphonazo III -based Mg2+ Complex in Aqueous Solution via Indicator
Mahiro Shimizu1, Shunichi Aikawa2, Yasumasa Fukushima3
1Faculty of Science and Engineering, Toyo University, 2100 Kujirai, Kawagoe, Saitama, 350-8585, Japan.
Abstract:
A simple and effective colorimetric detection of adenosine 5-triphosphate (ATP) in 100% aqueous media was developed based on an indicator displacement approach (IDA). A commercially available dye, Chlorophosphonazo III (CPA), was utilized as the indicator and the ATP detection was achieved using the complex of CPA with Mg2+ in a 2:1 stoichiometric ratio (CPA2-Mg2+) through the regeneration of CPA by the binding of ATP to Mg2+. Upon addition of a series of anions to the CPA2-Mg2+ complex, only the appearance of the solution of the complex with ATP exhibited a color change from blue to purple which can be detected by the naked eye. Moreover, the ATP recognition was not hampered by the presence of other anions. Hence, CPA2-Mg2+ is efficient in ATP highly selective and sensitive colorimetric detection in 100% aqueous media.
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