Graphene/fluorescein dye-based sensor for detecting As(III) in drinking water

Area of Science:

• Materials Science
• Nanotechnology
• Environmental Chemistry

Background:

• Arsenic(III) contamination in drinking water poses a significant global health risk.
• Accurate and sensitive detection methods for arsenic are crucial for public health and environmental monitoring.
• Existing methods for arsenic detection can be complex or lack the required sensitivity for trace levels.

Purpose of the Study:

• To develop and characterize a novel nanosensor for the sensitive detection of arsenic(III) in drinking water.
• To evaluate the sensing performance and mechanism of the reduced graphene oxide-fluorescein dye complex.
• To compare the nanosensor's capabilities with existing commercial field kits.

Main Methods:

• Preparation of a reduced graphene oxide (rGO) and fluorescein (FL) dye nanoparticle complex.
• Utilizing fluorescence quenching as the detection mechanism for arsenic(III).
• Employing time-resolved fluorescence spectroscopy and molecular modeling to investigate the quenching mechanism.

Main Results:

• The rGO-FL nanoparticle complex exhibited fluorescence quenching upon binding with arsenic(III).
• Two linear calibration ranges were established for arsenic(III) detection (0-4.0 mmol L⁻¹ and 4.0-10 mmol L⁻¹).
• A highly sensitive detection limit of 0.96 µg L⁻¹ was achieved, surpassing the WHO standard.

Conclusions:

• The developed rGO-FL nanosensor is a fast, sensitive, and accurate tool for detecting arsenic(III) in drinking water.
• The nanosensor demonstrates superior sensitivity compared to the current WHO standard for arsenic(III).
• This technology holds significant potential for environmental monitoring and public health applications.