Degradation Products and Impurities: Processes in Medical Devices
Many have the impression that medical devices and their components are immutable physical objects and remain on or in the body in the same condition that they are implanted or applied. This is not true, for the devices are subject to changes of either (or both) a chemical or physical nature (degradants) induced by the host organism (patient) or by the addition of chemical and physical materials during manufacturing, packaging, or manipulation during the application, implantation, or use (impurities). The detection, identication, quantication, and risk assessment of these moieties are described in Chapter 19. This chapter, however, considers how these are created or are introduced into or on a device.