Multi-detection of seratonin and dopamine based on an electrochemical aptasensor

Chemical stimuli that enable neurons to communicate with each other are called neurotransmitters. The task of these stimulants is to transmit the messages of neurons to target cells. In this work, a multi-detection mode electrochemical aptasensor system was developed for the neurotransmitters dopamine (3,4-dihydroxyphenylethylamine, DA) and serotonin (5 hydroxytryptamine, SER), which are associated with motivation-based learning, motor control, addiction, activation, arousal, immunity, central nervous systems. These neurotransmitters are related to many diseases, such as depression, primary pulmonary hypertension, kidney disease, Alzheimer's, Huntington's, and Parkinson's. This study used aptamer, a nucleic acid-based biorecognition agent, to capture the target molecules from complex matrix samples. After the capturing procedures, an electrochemical method (differential pulse voltammetry) was performed to observe the specific oxidation profiles of DA and SER. The developed multi-detection mode biosensor system had a linear response from 0.1 to 4 mu M with detection limits of 0.06 mu M for DA and 0.12 mu M for SER. In addition, real serum analyses were performed in the prepared direct electrochemical aptasensor system, and 86-92% of recovery values were observed. As a general conclusion, the main drawback of the multi-detection mode-based methods, sensitivity, can be solved by the aptamer binding process as implemented in this work.