Biodegradable asparagine-graphene oxide free chlorine sensors fabricated using solution-based processing

Area of Science:

• Materials Science
• Electrochemistry
• Environmental Science

Background:

• Chlorine is a vital disinfectant in water and food industries.
• Accurate detection of free chlorine is crucial for public health and safety.
• Existing chlorine sensors may have limitations in biodegradability or selectivity.

Purpose of the Study:

• To develop a novel, biodegradable free chlorine sensor.
• To functionalize graphene oxide (GO) with asparagine for sensor fabrication.
• To evaluate the sensor's performance characteristics, including sensitivity, selectivity, and stability.

Main Methods:

• A solution-based fabrication process was employed.
• Asparagine was functionalized onto graphene oxide (GO).
• The sensor was fabricated by drop-casting the ink onto a screen-printed carbon electrode (SPCE) and drying.

Main Results:

• The sensor demonstrated high sensitivity (0.30 μA ppm⁻¹) in a linear range of 0–8 ppm.
• A hysteresis-limited resolution of 0.2 ppm was achieved.
• The sensor exhibited excellent selectivity and stability over 16 hours and a temperature range of 10–45 °C.

Conclusions:

• The asparagine-functionalized GO sensor is a promising biodegradable alternative for free chlorine detection.
• The sensor's performance meets requirements for practical applications in water and food safety.
• This fabrication method offers a scalable approach for developing advanced electrochemical sensors.