Rapid Detection of the Biomarkers for Carcinoid Tumors by a Water Stable Luminescent Lanthanide Metal-Organic Framework Sensor

Serotonin (5-hydroxytryptamine, HT), a neurotransmitter, and its main metabolite 5-hydroxyindole-3-acetic acid (HIAA) are biomarkers for carcinoid tumors. They can be quantitatively detected by a new luminescent sensor based on a water stable lanthanide metal-organic framework (Ln-MOF). This Ln-MOF features a (3,4)-connected topology containing 1D channels occupied by lattice water molecules. Luminescent studies reveal that high luminescence quenching efficiency occurs upon the addition of HT and HIAA. The Ln-MOF also displays excellent sensitivity with fast response within 1 min, good reusability, and detection limits as low as 0.66 and 0.54 x 10(-6) M for HT and HIAA, respectively. In addition, the sensing function exhibits excellent selectivity even in the presence of other neurotransmitters and the main coexisting species in blood plasma and urine.