Silicon Oxynitride Coatings Are Very Promising for Inert and Durable Pharmaceutical Glass Vials

Glass packaging of novel medicinal molecules is challenged by hydrolysis of the glass network from an interaction with the stored drug, likely to result in leaching of constituent elements of the glass into the solution. We have succeeded in applying chemical-vapor-deposited silicon oxynitride coatings from a highly reactive trisilylamine derivative molecule as a precursor, at a temperature below 580 °C, opening up the possibility utilizing such coatings on glass surfaces. We demonstrate that such silicon oxynitride coatings applied on the internal surface of pharmaceutical vials prevent degradation, providing chemical inertness and withstanding severe screening conditions of the United States Pharmacopeia USP chapter. Fine structural determination and atomistic modeling of the Si–O–N network of the films confirm the nitrogen substitution of oxygen and densification of the silicate network through the addition of the former. The achieved barrier properties and excellent performance of these coatings pave the way toward sustainable packaging with improved product shelf life, transferable to multiple applications of surface coatings.