Label-Free Electrochemical Aptasensor for the Determination of Serotonin

A label-free electrochemical aptasensor was fabricated for the determination of serotonin (5-HT) by the employment of specific binding between 5-HT and aptamer and directly electrochemical measurement of 5-HT oxidation. The comparison between two aptasensors and two strategies was studied. An electrochemical aptasensor fabricated using 57-mer aptamer was facilely used to determine 5-HT in the range from 1 mu M to 100 mu M with detection limit of 0.3 mu M via one step recognition and detection. This work demonstrates that electrochemical method combing aptamer recognition and 5-HT oxidation provides an alternative and promising method for the determination of 5-HT with good selectivity and simplicity.