A simple micro-assay for inorganic phosphate

doi:10.1016/0003-2697(76)90071-3

Analytical Biochemistry

Volume 75, Issue 1, September 1976, Pages 201-210

https://doi.org/10.1016/0003-2697(76)90071-3 Get rights and content

Abstract

Modification of two assay procedures (Van Belle, H. (1970) Anal. Biochem.33, 132–142 and Itaya, K., and Ui, M. (1966) Clin. Chim. Acta14, 361) has allowed the development of a manual assay for inorganic phosphate of high simplicity and sensitivity. Total analysis requires only three reagents and is accomplished in less than 5 min, and smaples containing less than 1 μg/ml of inorganic phosphate may be detected. This assay retains a unique principle of the former two, complexation (instead of reduction) of the phosphomolybdate heteropoly complex with an appropriate triphenylmethane dye (malachite green, methyl green). Use of detergents has been eliminated and some further properties of the dyes, the assay, and the latter's applicability to a coupled enzyme system for phosphomonoester and phosphodiester analysis are discussed. Consideration is also given to the associated phenomena of transphosphorylation. (Dayan, J., and Wilson, I. B. (1964) Biochim. Biophys. Acta81, 620–623).

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A simple micro-assay for inorganic phosphate

Abstract

Anal. Biochem

Clin. Chim. Acta

J. Biol. Chem

Ukr. Kim. Zh

Anal. Chem

Anal. Chem