Enhancing electrochemical nitrite sensing with a novel nanocomposite of activated carbon/carbon cloth derived from microbial biofilm

• Published in: Biosensors & bioelectronics 2023-12, Vol.241, p.115659-115659, Article 115659
• Main Authors: Thatikayala, Dayakar, Min, Booki
• Format: Article
• Language: English
• Subjects: Biofilm-derived activated carbon; Carbon cloth; Electrochemical sensing; Nitrite; Wastewater
• ISSN: 0956-5663; 1873-4235
• DOI: 10.1016/j.bios.2023.115659

A novel approach was employed to fabricate a biofilm-derived activated carbon (BioAc) electrode on a carbon cloth (Cc) substrate for electrochemical nitrite sensing in water samples. The biofilm/Cc electrode was developed using a bioelectrochemical reactor, featuring a three-electrode system with nutrient media and microbial sources. The resultant biofilm electrode was activated at 450 °C for 2 h to eliminate impurities and enhance porosity. Morphological analysis of the BioAc/Cc electrode revealed a surface characterized by a compact film composed of numerous carbon nanoparticles. X-ray diffraction (XRD) analysis exhibited broad, highly crystalline peaks, enhancing both the electrode surface area and conductivity. Amperometry tests on the modified BioAc/Cc electrodes demonstrated a detection limit of 0.015 μM, a sensitivity of 1946.54 μA mM−1 cm−2, and a linear range spanning 0.35–478.21 μM at neutral pH conditions. Moreover, the electrodes demonstrated good stability with a RSD of 2.25% after 60 days and high reproducibility with an RSD of 1.64%. Real-time results showed 99.2 and 100.1% recovery for tap water and drinking water, respectively, highlighting the potential for commercialization in the future. These findings suggest that the BioAc/Cc electrode holds substantial potential for precise nitrite detection in environmental and wastewater applications. [Display omitted]