Multipurpose solutions (MPS) now make up the vast majority of the market for contact lens care solutions. Contact lens solutions have a complex role in contact lens wear; the name Multi-purpose Solution (MPS) gives an indication of that point. The influence of silicone hydrogel materials can be seen in an increased complexity in MPS composition. An important aspect of this complexity is the choice of surfactant - used either singly or in combination. Three important elements of solution behaviour are influenced by surfactants: Cleaning, comfort and compatibility.
The removal of lipids and proteins from a lens surface by a MPS can be broken down into three distinct phases.
• The lowering of the liquid phase surface tension
• Emulsification of the deposit
• Surface adsorption to prevent re-deposition