Lanthanide Metal-Organic Framework-Based Fluorescent Sensor Arrays to Discriminate and Quantify Ingredients of Natural Medicine

The discrimination and quantification of the ingredients from natural medicines are a challenging issue due to their complicated and various structures. Metal-organic frameworks (MOFs) have shown great promise in sensing applications. Here, we report a fluorescent sensor array for rapid identification of some natural compounds using a sensor array composed of four kinds of lanthanide (Eu3+ and Tb3+) fluorescent MOFs (Ln-MOFs), which have diversified fluorescent responses to 26 active/toxic compounds including 12 saponins, 7 flavonoids, 3 stilbenes, and 4 anthraquinones. The fluorescence of the Ln-MOFs after reaction with the compounds was summarized as datasets and processed by principle component analysis (PCA) and hierarchical cluster analysis (HCA) methods. The corresponding responses of the 4 types of compounds are well separated on 2D/3D PCA score plots and HCA dendrograms. We have also tested typical blind samples by concentration-dependent PCA, and an accuracy of 100% was obtained. In addition, the response mechanisms of the Ln-MOFs to the compounds were also studied. Compared with traditional methods using liquid chromatography-mass spectrometry, the developed fluorescent sensor array provides a more efficient and economic strategy to discriminate various active/toxic ingredients in natural medicine.

Automated summary

The research found that a fluorescent sensor array composed of four kinds of lanthanide (Eu3+ and Tb3+) fluorescent MOFs could rapidly identify and distinguish active/toxic ingredients in 26 natural compounds, with data processed using PCA and HCA methods to separate the responses of four types of compounds successfully. Compared to traditional methods, this developed fluorescent sensor array offers a more efficient and cost-effective strategy.