Chitosan-based antimicrobial filter media for point-of-use water treatment: a proof-of-concept study

Area of Science:

• Materials Science
• Environmental Science
• Microbiology

Background:

• Decentralized point-of-use (POU) water treatment faces challenges in microbial removal, especially viruses.
• Chitosan is a promising biopolymer for antimicrobial applications due to its properties.

Purpose of the Study:

• To develop and evaluate chitosan-based filter media for microbial removal in POU water treatment.
• To assess the performance of chitosan beads, electrospun nanofibres, and chitosan-coated sheep wool against bacteria and viruses.

Main Methods:

• Three chitosan-based filter media were synthesized: chitosan beads, electrospun nanofibres, and chitosan-coated sheep wool.
• Microbial removal efficiency was tested using model organisms: Escherichia coli (bacteria) and MS2 bacteriophages (viruses).
• Durability and reusability were assessed through wash cycles for chitosan-coated sheep wool.

Main Results:

• All chitosan-based media demonstrated high microbial removal performance.
• Chitosan beads showed superior bacterial and viral removal compared to traditional media like silica sand.
• Chitosan nanofibres achieved complete initial removal of E. coli and MS2, but showed structural fragility.
• Chitosan-coated sheep wool exhibited enhanced antibacterial performance, retaining >90% E. coli removal after 95 washes.

Conclusions:

• Chitosan exhibits versatility across different material formats for effective microbial control.
• Chitosan-based materials are a sustainable and efficient platform for POU water treatment.
• Further development is needed for practical implementation in decentralized water systems.