Early detection of cancer tumors can improve quality of life and chance of patient survival. Serotonin (5-hydroxytryptamine, HT) and 5-hydroxyindole-3-acetic acid (HIAA) are biomarkers of carcinoid tumors, but sensitive, selective, and facile detection methods for these are required.
In their article in Advanced Functional Materials, Prof. Wei Shi and Prof. Peng Cheng from Nankai University and the Collaborative Innovation Center of Chemical Science and Engineering in Tianjin, China, and their co-workers demonstrate a luminescent sensor based on a lanthanide metal–organic framework (Ln-MOF) for the detection of HT and HIAA at normal and dangerous levels.
The Ln-MOF used in the study, {[Eu(TDA)(H2BTEC)0.5(H2O)3]·H2O}n, is composed of Eu3+ ions coordinated to sensitizers of Eu3+ luminescence—thiazolidine 2,4-dicaboxylic acid (TDA2−) and 1,2,4,5-benzenetetracarboxylic acid (H2BTEC2−) anions.
Red emission of the Ln-MOF is observed by the naked eye under 254 nm irradiation. The structure was found to be stable and insoluble in water for 48 hours, and stable over a range of pH 4–11.
Incremental addition of trace amounts of HT and HIAA to an aqueous suspension of the Ln-MOF resulted in gradual luminescence quenching of the Ln-MOF, as seen by a color change from red to colorless under 254 nm illumination. The limits of detection for HT and HIAA were lower than the danger levels for carcinoid tumors, making this Ln-MOF suitable for early diagnosis of cancer.
The addition of typical substances found in blood plasma and urine to a solution of the Ln-MOF did not affect its luminescence intensity, and in the presence of HT and HIAA, the typical luminescence quenching of Ln-MOF was unaffected.
To find out more about this Ln-MOF for carcinoid tumor diagnosis, please visit the Advanced Functional Materials homepage.
