Electrochemical detection of 5-hydroxytryptamine using sustainable SnO2-Graphite nanocomposite modified electrode

•Novel sensing activity of SnO2-graphite nanocomposite on 5-HT was presented.•The electro active surface area was found to be 349.30 cm2/g.•The So-Sn-G electrode has positive sensing effects over 5-HT.•Overall, an increase in current signal and decrease in overpotential was noted. The precise function of serotonin and dopamine hugely influence the drug specification and treatment. Serotonin receptors or 5-hydroxytryptamine (5-HT) actively participate in neuro transmission and influence various biological and neurological functions. Considering its importance benefiting the detection and development, herein, SnO2, a thermally stable and conductive material was prepared by multi-step synthesis protocol and used for the sensing of 5-HT. Besides, graphite being an effective electron promoter and active catalyst was synthesised using a sustainable approach and composited with SnO2. The electrochemical detection of 5-HT was done with SnO2-G nanocomposite, and modified silicone-SnO2-G nanocomposite electrode. The addition of graphite nanoflakes substantially improves the response behaviour of So-Sn-G electrode with the calculated electroactive surface area of 0.291 cm2. Further, the cyclic voltammetry plots at various scan rate shows the reduced over-potential (0.6628 V) and improved response of current signals (4.314 μA) owing to synergistic electrocatalytic activity of the So-Sn-G electrode. The differential pulse voltammetry reveals the linearity and improved detection limit with correlation coefficient of 0.9944, owing to excellent detection of 5-HT for prolonged duration.