Microfibrillated cellulose-based colorimetric sensor strips for detecting total iron in water

Area of Science:

• Materials Science
• Environmental Science
• Analytical Chemistry

Background:

• Microfibrillated cellulose (MFC) is a sustainable biomass-derived material with properties suitable for chemical sensor development.
• Existing methods for iron detection can be costly or complex, necessitating simpler alternatives.

Purpose of the Study:

• To develop and evaluate cost-effective, cellulose-based sensor strips for the colorimetric detection of total iron in water.
• To utilize microfibrillated cellulose functionalized with 1-(2-Thiazolylazo)-2-naphthol (TAN) for iron sensing.

Main Methods:

• Fabrication of MFC casting membranes functionalized with TAN.
• Characterization of MFC@TAN strips using structural and morphological techniques.
• Evaluation of sensing performance via digital image colorimetry for total iron detection.

Main Results:

• The MFC@TAN strips achieved limits of detection of 0.08 mg L⁻¹ (Blue channel, 5 min) and 0.09 mg L⁻¹ (Red channel, 30 min).
• The sensor accurately detected total iron in tap water within the 0.08-0.70 mg L⁻¹ range, comparable to standard methods.
• MFC@TAN strips demonstrated enhanced sensing performance over commercial papers due to their porous structure facilitating dye immobilization and iron reaction.

Conclusions:

• The developed cellulose-based sensor strips offer a simple, low-cost, and effective method for total iron determination in water.
• These MFC@TAN strips show significant potential for routine environmental water analysis and quality monitoring.