Li Li, Guo Ruibin, Zhang Dongxia, Du Xinzhen
College of Chemistry and Chemical Engineering, Northwest Normal University, Lanzhou, 730070, China.
Key Lab of Bioelectrochemtry Environmental Analysis of Gansu, Lanzhou, 730070, China.
Luminescence. 2015 Aug;30(5):512-8. doi: 10.1002/bio.2769. Epub 2014 Oct 1.
A novel galangin-potassium permanganate (KMnO4)-polyphosphoric acid (PPA) system was found to have an outstanding response to tryptophan (Trp). Trp determination using this KMnO4 -PPA system was enhanced significantly in the presence of galangin. A highly sensitive flow-injection chemiluminescence (CL) method to determine Trp was developed based on the CL reaction of galangin-KMnO4 -Trp in PPA media. The presence of galangin, a member of the flavonol class of flavonoid complexes, greatly increased the luminous intensity of Trp in KMnO4 -PPA systems. Under optimized conditions, Trp was determined in the 0.05-10 µg/mL range, with a detection limit (3σ) of 5.0 × 10(-3) µg/mL. The relative standard deviation (RSD) was 1.0% for 11 replicate determinations of 1.0 µg/mL Trp. Two synthetic samples were determined selectively with recoveries of 98.4-100.1% in the presence of other amino acids. The possible mechanism is summarized as follows: excited states of Mn(II)() and Mn(III() types are the main means of generating chemical luminescent species, and Trp concentration and luminescence intensity have a linear relationship, which enables quantitative analysis.
一种新型的高良姜素-高锰酸钾（KMnO₄）-多聚磷酸（PPA）体系被发现对色氨酸（Trp）有出色的响应。在高良姜素存在的情况下，使用该KMnO₄-PPA体系测定Trp的效果显著增强。基于高良姜素-KMnO₄-Trp在PPA介质中的化学发光（CL）反应，开发了一种用于测定Trp的高灵敏度流动注射化学发光（CL）方法。黄酮类化合物复合物中黄酮醇类的成员高良姜素的存在，极大地提高了KMnO₄-PPA体系中Trp的发光强度。在优化条件下，Trp的测定范围为0.05 - 10μg/mL，检测限（3σ）为5.0×10⁻³μg/mL。对1.0μg/mL的Trp进行11次重复测定时，相对标准偏差（RSD）为1.0%。在存在其他氨基酸的情况下，对两个合成样品进行了选择性测定，回收率为98.4 - 100.1%。可能的机理总结如下：Mn(II)*和Mn(III)*类型的激发态是产生化学发光物种的主要方式，并且Trp浓度与发光强度具有线性关系，这使得能够进行定量分析。
