Application of a Sonogel-Carbon electrode modified with gold nanoparticles synthesized through a green technique and pine leaf extract for the simultaneous determination of neurotransmitters

This paper reports a Sonogel-Carbon electrode modified with pine leaf extract-derived gold sononanoparticles (AuSNPs) for the simultaneous detection of serotonin (5-HT) and dopamine (DA), key neurotransmitters in human health. To our knowledge, this is the first time AuSNPs have been greenly synthesized using pine leaf extract coupled with ultrasound technology in only a few minutes. The obtained AuSNPs (56 ± 14 nm) were characterized through several techniques: UV/vis spectroscopy, Fourier infrared spectroscopy, X-ray energy dispersive spectroscopy, and electron microscopy. The green AuSNPs were drop-cast onto the Sonogel-Carbon electrode (SNGCE) for the simultaneous determination of DA and 5-HT. The proposed sensor exhibited low limits of detection, good sensitivity (421.80 pM for DA and 192.55 pM for 5-HT), and reproducibility (RSD 4%). Proof of concept was demonstrated by their successful detection in human blood serum, obtaining recovery rates close to 100% for both analytes in all cases, demonstrating that this sensor has great potential for applications in neurodegenerative diseases and early-stage cancer diagnosis.