A composition for rendering a hydrophobic surface hydrophilic. A hydrophobic binder, typically a silicone compound such as a siloxane, attaches hydrophilic sol-gel particles to the surface, such as hydrophobic regions of a silicone contact lens. Hydrophilic regions are preferably unmodified. The binder attaches to the particles via functional groups, and can autoadhere to the hydrophobic surface. A coating of the composition can be deposited from solution at ambient or room temperature, allowing coating of temperature sensitive substrates. Such coatings can withstand heating (such as for sterilization) in acidic solutions, retaining their hydrophilic properties.