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Preparation of 2-nitro-5-thiobenzoate for the routine determination of reagent hypochlorous acid concentrations
Thomas M Jeitner1, Mike Kalogiannis, Jim Mathew
1Winthrop University Hospital, Mineola, NY 11501, USA.
Abstract:
Solutions of hypochlorous acid (HOCl) decay over time. This decay indicates the necessity for methods and reagents for the routine measurement of this oxidant. 2-Nitro-5-thiobenzoate is commonly used to measure HOCl concentrations. This article describes a method for the preparation of 2-nitro-5-thiobenzoate that is stable for at least 3 months. This method relies on the partial rather than full reduction of 5,5'-dithiobis-(2-nitrobenzoic acid) and the resulting equilibrium between the substrate and the product.
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