A method of making component for a medicinal delivery device comprises applying a primer composition to at least a portion of the surface of a component of a medicinal delivery device, where the primer composition comprises a silane having two or more reactive silane groups separated by an organic linker group. The method further comprises applying a coating composition to the portion of the surface of the component, where the coating composition comprises an at least partially fluorinated compound. A method of making a component for a medicinal delivery device comprises cleaning at least a portion of the surface of the component using a solvent comprising a hydrofluoroether of formula as defined herein, followed by the application of an at least partially fluorinated coating composition to the cleaned portion of the surface. A coated component for a medical delivery device comprises a fluorine containing coating having two layers: a first polyfluoropolyether-containing layer comprising silane entities as defined in Formula Ib herein, which shares at least one covalent bond with a second non-fluorinated layer comprising entities of Formula IIb as defined herein. The coated component may have reduced dose variability and unit to unit variability.
