Development of a Novel Electrochemical Biosensor Based on Organized Mesoporous Carbon and Laccase for the Detection of Serotonin in Food Supplements

Serotonin is a biogenic amine that has multiple roles in the human body and is mainly known as the happiness hormone. A new laccase (Lac)-based biosensor has been developed for the qualitative and quantitative determination of serotonin in three dietary supplements from three different manufacturers. The enzyme was immobilized on an organized mesoporous carbon-modified carbon screen-printed electrode (OMC-SPE) by the drop-and-dry method, the active surface being pretreated with glutaraldehyde. With the new biosensor, serotonin was selectively detected from different solutions. Square-wave voltammetry was the technique used for the quantitative determination of serotonin, obtaining a detection limit value of 316 nM and a quantification limit value of 948 nM in the linearity range of 0.1-1.2 mu M. The pH for the determinations was 5.2; at this value, the biocatalytic activity of the laccase was optimal. At the same time, the electrochemical performance of the OMC-SPE/Lac biosensor was compared with that of the unmodified sensor, a performance that highlighted the superiority of the biosensor and the very important role of the enzyme in electrodetection. The results obtained from the quantitative determination of serotonin by square-wave voltammetry were compared with those from the FTIR method, revealing a very good correlation between the results obtained by the two quantitative determination methods.

Automated summary

A new Lac-based biosensor has been developed to qualitatively and quantitatively determine serotonin in dietary supplements. The biosensor showed selective detection capabilities and superior electrochemical performance. The quantitative determination of serotonin by square-wave voltammetry showed good correlation with the FTIR method.