A Flavin Derivative-Based Fluorometric Analysis for the Diabetes Mellitus Inducer, Alloxan, for Its Follow-up in Flour and Flour-Derived Food

Abstract

Alloxan is a toxic substance that is used as a diabetogenic agent in experimental animals and was found to be toxic to the kidney as well. Alloxan is speculated to be produced during the bleaching process of wheat flour, and there are no confirmations about its presence in the bread or other flour-derived foods. In this study, we intended to explore the presence of alloxan in all-purpose flour, as well as its extension to flour-derived food, by a highly selective, cost-effective, and fully validated spectrofluorometric method. The utilized method is based on the derivatization of alloxan with 1,2-diaminobenzene in acidic medium to produce a flavin fluorescent derivative. The structure of the formed flavin derivative was confirmed by tandem mass spectrometry. The method showed a linear response for alloxan in the range of 0.1–9.0 μg/mL, with a detection limit of 27 ng/mL. In addition, the utilized fluorometric method was found to be eco-friendly when tested with green chemistry metrics. Furthermore, the method was applied successfully for the determination of alloxan in different flour types with good recoveries that ranged from 88.1 to 96.1%. Alloxan concentrations in the bleached flour samples ranged from 0.43 to 0.83 μg/g. However, when the method was applied to flour-based food samples such as spaghetti, noodles, bread, rice, and white sugar, alloxan was not detected in all of them. This might be attributed to the destruction of alloxan during the baking and other preparation processes of these food products.