Biosensors 1 Coated glass substrates 1 Device sensitivity 1 Glass 1 Hydrogels 1 Interfaces (materials) 1 Metal cladding 1 Metal coatings 1 Metal-clad leaky waveguides Optical bio-sensors 1 Optical characteristics 1 Refractive index 1 Refractive index changes 1 Silanizations 1 Substrates 1 Surface treatment 1 Titanium 1 Waveguides 1 Waveguiding films 1 acrylate hydrogel 1 metal clad leaky waveguide 1 optical biosensor 1 silanization 1