Understanding the Concept:
The choice of sterilization method depends on the physical properties and material composition of the product. The method must destroy microbial contamination without degrading the product itself.
Material Compatibility Assessment:
• Autoclaving & Dry Heat (Thermal Methods): Disposable plastic syringes are typically manufactured from thermoplastics such as polypropylene or polystyrene. These materials have low melting points and will warp, melt, or degrade when subjected to the high temperatures required for autoclaving ($121^{\circ}\text{C}$) or dry heat ($160^{\circ}\text{C}$--$170^{\circ}\text{C}$).
• Ultraviolet (UV) Irradiation: UV light has low penetrating power and only sterilizes exposed surfaces. It cannot penetrate through packaging or internal syringe parts like the plunger and barrel interfaces.
• Ethylene Oxide (EtO) Sterilization: A low-temperature gaseous sterilization method. EtO gas penetrates porous packaging materials and effectively alkylates microbial DNA and proteins. Because it operates at low temperatures, it is ideal for heat-sensitive plastic medical devices and disposable syringes.
Consequently, Ethylene oxide sterilization is the most appropriate method.