Selective fluorescence determination of chromium(VI) with poly-4-vinylaninline nanoparticles

Area of Science:

• Analytical Chemistry
• Materials Science

Background:

• Chromium VI (Cr(VI)) is a toxic environmental pollutant requiring sensitive detection methods.
• Existing methods for Cr(VI) determination can be complex, requiring separation from Cr(III).
• Fluorescent nanoparticles offer potential for sensitive and selective analyte detection.

Purpose of the Study:

• To develop a selective and sensitive method for determining Cr(VI) in aqueous samples.
• To utilize the fluorescence quenching properties of poly-4-vinylaniline nanoparticles (PVN) for Cr(VI) detection.
• To establish a rapid, one-step assay for Cr(VI) quantification without Cr(III) separation.

Main Methods:

• Synthesis of poly-4-vinylaniline nanoparticles (PVN) via ultrasonic radiation.
• Investigation of fluorescence quenching of PVN by Cr(VI) under varying reaction conditions.
• Development of a spectrofluorometric assay for selective Cr(VI) determination.

Main Results:

• The PVN nanoparticles exhibited strong fluorescence.
• A linear calibration curve for Cr(VI) was obtained from 0.1-13.0 microg/mL (R²=0.9984).
• A low limit of detection (0.02 microg/mL) was achieved with a short reaction time (<1 min) and stable signals (>2.5 h).
• The method demonstrated selectivity for Cr(VI) in the presence of Cr(III) and was successfully applied to synthetic and wastewater samples.

Conclusions:

• The proposed method provides a simple, rapid, and selective approach for Cr(VI) determination in water.
• PVN nanoparticles are effective fluorescent probes for the sensitive detection of Cr(VI).
• This assay offers a practical alternative for environmental monitoring of Cr(VI).