Zwitterionic Nanocellulose-Based Membranes for Organic Dye Removal

Area of Science:

• Materials Science
• Environmental Science
• Nanotechnology

Background:

• Water contamination by organic dyes and pathogenic bacteria poses significant environmental and health risks.
• Development of efficient, eco-friendly nanomaterials is crucial for effective water remediation.
• Zwitterionic materials offer unique properties for pollutant adsorption and antimicrobial activity.

Purpose of the Study:

• To synthesize and characterize novel zwitterionic nanocomposite membranes for water remediation.
• To evaluate the antibacterial efficacy of the membranes against pathogenic bacteria.
• To assess the performance of the membranes in removing cationic and anionic dyes from water.

Main Methods:

• One-pot polymerization of 2-methacryloyloxyethyl phosphorylcholine within a bacterial nanocellulose (BNC) matrix.
• Fabrication of cross-linked poly(2-methacryloyloxyethyl phosphorylcholine) (PMPC)/BNC nanocomposite membranes.
• Testing of thermal stability, mechanical properties, water uptake, antibacterial activity, and dye adsorption capacity.

Main Results:

• The PMPC/BNC nanocomposite membranes demonstrated high thermal stability (up to 250 °C) and mechanical strength (Young's modulus ≥ 430 MPa).
• High water uptake capacity (627%-912%) was observed across different pH levels.
• Significant reduction in bacterial concentration (4.3-log for Gram-positive, 1.8-log for Gram-negative) was achieved.
• Effective removal of methylene blue (cationic) and methyl orange (anionic) dyes, with adsorption capacities of approximately 4.4-4.5 mg g⁻¹.

Conclusions:

• The synthesized PMPC/BNC nanocomposite membranes exhibit excellent thermal and mechanical properties, along with high water absorbency.
• These membranes show potent antibacterial activity against common pathogenic bacteria.
• The PMPC/BNC nanocomposites are effective in removing both cationic and anionic dyes, indicating their potential as bio-based adsorbents for comprehensive water remediation.