ChEBE Faculty Research
Nehal Abu-Lail, Ph.D.
The use of Surface Chemistry to Control Bio-Adhesion
The fabrication of surfaces that can control bio-adhesion is of great significance to many different areas especially in water transfer systems, drug delivery, and applications in biomedical sciences such as preventing the formation of biofilms on medical implants. Stimulus responsive polymers (SRP's) are an excellent example on the materials that can be used to control bio-adhesion. SRP's are a set of environmentally switchable smart polymers that undergoes an inverse phase transition triggered by changes in the solvent quality such as temperature, pH, and ionic strength. Associated with this phase transition is a significant conformational change. Due to this phase transition and conformational change, these smart materials can be used to bio-chemically trigger attachment of cells.
In addition to the SPR's, the surface chemistry of the substrate or the AFM probe can be chemically modified to control bioadhesion. Self assembled monolayers of thiols can be used to change the hydrophilicity of the substrate to favor or prevent the attachment of bacteria to it. Finally, controlling the chemical composition of the substrate is extremely important in controlling bioadhesion especially from practical point of view. Bacterial adhesion usually occurs on surfaces that have been exposed to all different types of environments such as oxides, organic contaminates and pollutants, and different colloidal particles (sand, bacteria). Therefore, the goal of this part of my research will be to investigate the effect of substrate composition (hydrophobicity, polymer coatings, and thin charged films) on bacterial adhesion to different surfaces.
Example on the hydrophobic and hydrophilic states of pNIPAAM brushes, a typical example of stimulus responsive polymers.