Fast preparing bioelectrode with conductive bioink for nitrite detection in high sensitivity and stability.

Area of Science:

• Biotechnology
• Biosensor Technology
• Electrochemistry

Background:

• Electrochemically active biofilms (EABs) offer advantages for nitrite detection, including specificity, rapid response, and longevity.
• Current challenges in EAB application include difficulties in large-scale, uniform, and rapid production.

Purpose of the Study:

• To develop a novel, fast fabrication method for an EAB biosensor for nitrite detection using a synthetic biofilm electrode.
• To investigate the impact of conductive materials on the performance of the synthetic biofilm electrode.

Main Methods:

• Fabrication of a synthetic biofilm electrode by coating graphite sheets with bioinks containing conductive materials.
• Evaluation of the electrode's performance for nitrite detection, including incubation time, reproducibility, voltage enhancement, and current amplification.
• Characterization of the biosensor's detection range, sensitivity, and operational stability.

Main Results:

• The synthetic biofilm electrode demonstrated short incubation times and good reproducibility.
• Incorporation of conductive materials, such as carbon nanofibers, significantly enhanced electrode voltage (up to 633%) and nitrite reduction current (2.97-fold increase) by improving extracellular electron transfer (EET).
• The developed nitrite biosensor achieved a detection range of 0.1–15 mg NO₂^--N L^-1, high sensitivity (610.8 μA mM^-1 cm^-2), and stability over at least 280 cycles.

Conclusions:

• The study presents a practical and rapid approach for preparing highly sensitive and stable EAB sensors for nitrite detection.
• The findings offer valuable insights into the use of conductive materials for optimizing synthetic biofilms in biosensor development.
• This method facilitates the scale production and optimization of EAB-based biosensors.