Wang Zhuming, Chen Donghua, Gao Xin, Song Zhenghua
Key Laboratory of Synthetic and Natural Functional Molecule Chemistry of the Ministry of Education, College of Chemistry and Material Science, Northwest University, Xi'an 710069, China.
J Agric Food Chem. 2009 May 13;57(9):3464-9. doi: 10.1021/jf900132u.
A sensitive chemiluminescence method based on a luminol-myoglobin system is proposed for the determination of melamine in milk products. It was found that the mixed solutions of melamine and myoglobin could react to form a complex on line, which could greatly inhibit the chemiluminescence intensity generated from the reaction between luminol and myoglobin. The decrease in chemiluminescence intensity was proportional to the concentration of melamine, giving a calibration graph linear over the concentration from 10 pg mL(-1) to 50 ng mL(-1) (R(2) = 0.9988) with a detection limit of 3 pg mL(-1) (3sigma). At a flow rate of 2.0 mL min(-1), one analysis cycle, including sampling and washing, could be accomplished in 20 s with a relative standard deviation of <4.0%. The proposed method was applied successfully to the determination of melamine in milk products, and the recovery was from 93.4 to 106.5%. The possible mechanism of luminol-myoglobin-melamine reaction is given.
提出了一种基于鲁米诺 - 肌红蛋白体系的灵敏化学发光法用于测定奶制品中的三聚氰胺。研究发现，三聚氰胺与肌红蛋白的混合溶液能够在线反应形成一种络合物，该络合物可极大地抑制鲁米诺与肌红蛋白反应产生的化学发光强度。化学发光强度的降低与三聚氰胺的浓度成正比，在10 pg mL(-1)至50 ng mL(-1)的浓度范围内校准曲线呈线性（R(2)=0.9988），检测限为3 pg mL(-1)（3σ）。在流速为2.0 mL min(-1)时，一个包括进样和清洗的分析周期可在20 s内完成，相对标准偏差<4.0%。该方法成功应用于奶制品中三聚氰胺的测定，回收率为93.4%至106.5%。给出了鲁米诺 - 肌红蛋白 - 三聚氰胺反应的可能机理。
