A method for preparing sensing devices (biosensors) includes the steps of: (1) applying a photopatternable silicone composition to a surface in a sensing device to form a film, (2) photopatterning the film by a process comprising exposing the film to radiation through a photomask without the use of a photoresist to produce an exposed film; (3) removing regions of the non-exposed film with a developing solvent to form a patterned film, which forms a permselective layer or an analyte attenuation layer covering preselected areas of the sensing device.