Colorimetric Detection of ATP by a Chlorophosphonazo III -based Mg Complex in Aqueous Solution via Indicator Displacement Approach.

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 Mg in a 2:1 stoichiometric ratio (CPA-Mg) through the regeneration of CPA by the binding of ATP to Mg. Upon addition of a series of anions to the CPA-Mg 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, CPA-Mg is efficient in ATP highly selective and sensitive colorimetric detection in 100% aqueous media.