An efficient amperometric catechol sensor based on novel polypyrrole-carbon black doped α-Fe2O3 nanocomposite

Catechol reacts with a variety of biomolecules including DNA, proteins, membranes, etc. and thus causes irreparable damage to human health. Therefore, herein a highly sensitive and selective electrochemical catechol (CC) sensor based on a novel polypyrrole/carbon black doped alpha-Fe2O3 nanocomposite (PPy/CB/alpha-Fe2O3 NCs) modified glassy carbon electrode (GCE) is developed and demonstrated. The structural and morphological properties of the PPy/CB/alpha-Fe2O3 NCs were investigated by FESEM, TEM, EDS, XPS, XRD, FTIR, and Raman spectroscopy. This newly designed highly-sensitive PPy/CB/alpha-Fe2O3/GCE-based electrochemical sensor can measure a wide range of CC (0.5-1188 mu M) in phosphate buffer solution (PBS) with a sensitivity of 0.3521 mu A mu M-1 cm(-2) and a logical limit of detection (LOD) 52.8 +/- 0.1 nM. The selectivity of the proposed CC sensor was also examined in the presence of common interfering substances. Furthermore, the CC sensor electrode showed highly acceptable results towards the detection of CC level in real samples analysis by the standard addition method. This new combination of active materials, PPy/CB/alpha-Fe2O3 modified GCE exhibited excellent reproducibility, repeatability, and long-term stability during the electrochemical detection of catechol. Therefore, this approach will emerge as an effective technique in developing efficient electrochemical sensors to detect phenolic compounds for environmental safety.

Automated summary

A highly sensitive and selective electrochemical catechol sensor based on a novel nanocomposite-modified electrode has been developed and demonstrated. The sensor shows excellent reproducibility, repeatability, and long-term stability in detecting catechol levels in real samples, making it an effective technique for environmental safety.