A novel electrochemical sensor modified with green gold sononanoparticles and carbon black nanocomposite for bisphenol A detection

Herein, we report an eco-friendly electrochemical bisphenol A (BPA) sensor based on carbon black (CB) and gold sononanoparticles (AuSNPs) nanocomposite-modified Sonogel-Carbon electrode (SNGCE). The AuSNPs were synthesized by a novel green approach employing olive leaves extract and assisted by high energy ultrasound. The AuSNPs was characterized by UV–Vis, FTIR, SEM and STEM. The formation of AuSNPs was confirmed by UV–Vis, which showed an absorption peak at 532 nm. The FTIR analysis identified the bioactive molecules present in the olive leaves which were responsible for the bioreduction and capping of the nanoparticles. STEM results evidenced the polymorphic nature of the biosynthesized AuSNPs and the average size of about 14 ± 1, 39 ± 5 and 20 ± 1 nm, respectively for spherical, triangular and hexagonal nanoparticles. The CB/AuSNPs/SNGCE sensor for BPA determination showed higher electroactivity, with the highest sensitivity, and a rather low limit of detection (LOD, n = 3) of 60 nM at the BPA concentration range of 0.5–15 μM, thanks to the synergic combination of green AuSNPs and CB as cost-effective nanomaterials. Furthermore, our developed sensor showed an excellent selectivity towards different interferents. Besides, the analytical sensor was successfully applied for the determination of BPA in tap and mineral water samples. [Display omitted] •For the first time AuSNPs were synthesized using olive leaves by high energy ultrasound.•The green AuSNPs were characterized by UV–Vis, FTIR, SEM and STEM analysis.•A CB/AuSNPs/SNGCE electrochemical sensor was developed for BPA detection.•The CB/AuSNPs nanocomposite improved dramatically the sensitivity of the sensor.•The proposed sensor was successfully applied in water samples.