Selective detection of water pollutants using a differential aptamer-based graphene biosensor

Area of Science:

• Environmental Science
• Materials Science
• Analytical Chemistry

Background:

• Graphene field-effect transistor (GFET) sensors show promise for detecting water pollutants.
• Sensitivity to environmental variations and fabrication inconsistencies hinders GFET sensor application.
• Differential designs are challenging for GFETs due to fabrication and material property impacts.

Purpose of the Study:

• To develop a differential GFET affinity sensor for selective water pollutant detection.
• To minimize the impact of environmental condition variations on measurement accuracy.
• To mitigate variations from fabrication processes and material properties.

Main Methods:

• A differential GFET affinity sensor design was implemented.
• A compensation scheme for individual sensing units was introduced.
• The sensor was tested for 17β-estradiol detection in buffer and tap water with varying conditions.

Main Results:

• The differential GFET sensor effectively detected 17β-estradiol.
• Consistent results were achieved despite pH variations and unknown interferences in tap water.
• The sensor design minimized nonspecific disturbances, enabling selective detection.

Conclusions:

• The differential graphene affinity sensor successfully mitigates nonspecific interferences.
• This technology enables selective water pollutant detection for improved water quality monitoring.
• The compensation scheme addresses fabrication and material variations, enhancing sensor reliability.