Laboratory of Physical Chemistry of Environmental Engineering and Biology, Faculty of Science II, Lebanese University, P.O. Box 26110217, Fanar, Lebanon.
Talanta. 2013 Nov 15;116:277-82. doi: 10.1016/j.talanta.2013.05.035. Epub 2013 May 24.
The objective of this study was to develop a spectrofluorimetric method for the quantitative determination of melamine. The method was based on the complexation of melamine with a mixture of formaldehyde and chemicals including a ketone group, as described by the Mannich reaction. The complex was determined by spectrofluorimetric measurement as it is characterized by specific spectroscopic properties that are related to the chromophore of the ketone compounds. 1,3-Diphenylpropane-1,3-dione (DPPD) was tested as a ketone compound. The fluorescence spectrum of the complex presented a maximum of absorption at 325 nm.A quenching of the fluorescence occurred when melamine was added into the solution. The kinetic of fluorescence quenching was followed to determine quantitatively the melamine concentration. An internal standard was added to quantify melamine. The method was tested to determine the level of melamine in contaminated milk powder. The recovery value was 97% and the limit of detection was 0.007 μg mL(-1.)
本研究旨在开发一种用于定量测定三聚氰胺的分光荧光法。该方法基于三聚氰胺与甲醛和包括酮基在内的化学物质的混合物的络合反应，如曼尼希反应所述。该络合物通过分光荧光测量来确定，因为它具有与酮化合物的生色团相关的特定光谱特性。1,3-二苯基丙烷-1,3-二酮（DPPD）被测试为一种酮化合物。当三聚氰胺加入溶液中时，复合物的荧光光谱在 325nm 处呈现最大吸收。荧光猝灭发生。跟踪荧光猝灭的动力学以定量确定三聚氰胺的浓度。加入内标以定量三聚氰胺。该方法已用于检测受污染奶粉中的三聚氰胺含量。回收率为 97%，检测限为 0.007μgmL(-1)。
