Techniques Characteristics
Physiochemical methods Blending Simple adsorption of functionalized additives to surface
Acid etching
Surface roughening Surface oxidation
Plasma treatments
“Dry” surface engineering technique Effective and universal method for all types of organic surfaces Introduction of reactive functional groups on the surface
Plasma sputtering & etching Materials/impurities removal Surface roughening
Plasma polymerization Thin polymer films deposition Good adhesion between the substrate and deposited layer
Photon irradiation
Feasible to small and localized area Highly accurate surface topography altering Polar surface functional groups generation by controlled surface photo-oxidation
Ion-beam deposition
Surface patterning Effective in controlling hydrophilic/hydrophobic balance Optimal durability of the modified surface
Lithography Photolithography Ion lithography Electron lithography
Surface micro- & nano-structuring
Thin film coating Physical adsorption through weak forces (hydrogen bonding, van der Waals forces & electrostatic interaction)
Dip coating Simple and effective Homogeneous & smooth layer coating Controllable film thickness
Spin coating
Controllable film thickness
Langmuir-Blodgett Films
Possible multi-layer deposition with controlled internal structure
Layer-by-layer assembly Multi-layer deposition based on electrostatic interactions Suitable for various topography and structure
Covalent immobilization
Strong adhesion to the surface Reactive functional groups on surface required Surface pre-activation of chemically inert surface required
Biological methods (Biomolecules (BMs) immobilization)
Physical adsorption
No chemical modification included Unstable & reversable interactions between BMs and surface Potential steric hindrance to proteins & peptides with long sequence
Covalent immobilization
Strong attachment of BMs to surface Surface functional groups required