A simple and cost-effective distance-based paper analytical device for phosphate ion determination

Area of Science:

• Environmental Chemistry
• Analytical Chemistry
• Materials Science

Background:

• Phosphate monitoring in water is critical for environmental health, particularly to prevent eutrophication.
• Conventional methods for phosphate detection are often complex, expensive, and require specialized equipment and trained personnel.

Purpose of the Study:

• To develop a simple, cost-effective, and rapid paper analytical device for quantifying phosphate ions in water sources.
• To provide an alternative on-site detection method for phosphate that is accessible and easy to use.

Main Methods:

• Development of a distance-based paper analytical device using a ferric ion (Fe3+), salicylic acid (SA), and polyethyleneimine (PEI) colorimetric indicator.
• Quantification of phosphate concentration based on the distance of color change observed visually.
• Validation of the device using the standard molybdenum blue method and analysis of spiked water samples.

Main Results:

• The developed device demonstrated a linear response for phosphate detection in the range of 5 to 75 mg/L (R2 = 0.9954).
• A naked-eye detection limit of 2 mg/L was achieved, which could be improved to 0.2 mg/L with a preconcentration step.
• Statistical analysis showed no significant difference compared to the molybdenum blue method, with recoveries between 85.05% and 117.97%.

Conclusions:

• The proposed paper analytical device is a viable, accurate, and rapid tool for on-site phosphate monitoring in water.
• This method offers a cost-effective and user-friendly alternative to conventional phosphate detection techniques.
• The device's performance and validation support its application in environmental monitoring and water quality assessment.