• Biofouling control by zwitterionic polymer brushes: Interactions between bacteria and ultralow fouling surfaces

Objective

Fabricate zwitterionic diblock copolymer aimed to modify surfaces and membranes that will provide us with optimal reduction of biofouling propensity.

Technical Approach

Synthesizing the block-copolymer, polystyrene bonded to the alternating peptide lysine-glutamic acid (PS-b[(KE)alt]15), to prove its self assembly on Polystyrene surfaces to analyze its interactions with bacteria and biofilms.

Accomplishments

  • Formation of the PS-b-[(KE)alt]15 brush was analyzed including the layer hydration (swelling) and the related anti-polyelectrolytic effects
  • Anti-biofouling properties were elucidated:
    1. extracellular polymeric substances (EPS) adsorption
    2. bacterial attachment
    3. mono-culture biofilm formation.
  • All these biofouling related processes were significantly affected.

Next Steps

  • Viscoelastic properties of the brush will be compared to the QCM-D results
  • Effects of brush density and polymer size will be elucidated
  • RO membranes will be modified and tested

Impact

  • A paper is currently in preparation process on mitigation of biofouling by PS-b[(KE)alt]15 BCP
  • A short lecture was conducted in the ACS workshop: “Advances in Materials and Processes for Polymeric Membrane Mediated Water Purification”, February 15-18, 2015, Asilomar Conference Grounds, Pacific Grove, California USA