Red Emitting Fluorescent EuDPA Complex as a Probe for the Detection of Serotonin, A Neurotransmitter.

Serotonin, a neurotransmitter and also a biomarker for Alzheimer's as well as Carcinoid Syndrome. It has two important roles in the human body - central as well as peripheral. In the central nervous system, it acts as a neurotransmitter and controls all the brain functions and as a peripheral hormone, it controls the functions of several organs in the body. Herein, we developed a Europium dipicolinic acid (EuDPA) based lanthanide luminescent complex with bright red fluorescence. This fluorescence is further used for the detection of Serotonin (ST). On adding ST, the fluorescence of the probe is quenched. Also, the developed probe shows good selectivity towards other neurotransmitters & co-existing biomolecules. A LoD of 0.99 nM is achieved with this probe. Sensing based on paper-strip was done to check the practicability of the probe, and a real sample analysis was also conducted from spiked human serum/urine samples.