When Silicone Oil Is Not an Option
Silicone oil is commonly used as a lubricant to facilitate plunger movement in glass syringes. It is well known that silicone oil can lead to the presence of subvisible particles in a drug product, and in the case of a protein-based drug product, might induce aggregates that diminish performance, or worse, induce immunogenicity.
Silicone poses another risk; it has been observed that silicone oil can actually infiltrate the patient during injection. This is especially problematic for ophthalmologic applications. Injections into the eye demand careful and precise application; a smooth and consistent delivery force profile is essential.
For an intravitreal injection, a small volume is typical, e.g., 50 µl. The maximum safe volume to inject without prior fluid removal is ~ 100-200 µl. Larger injection volumes are uncommon, with two exceptions: the injection of gas for pneumatic retinopexy and the injection of multiple intravitreal agents in one session. The question becomes how to achieve smooth/consistent delivery force without use of silicone oil.
West has an answer – a Daikyo Crystal Zenith® 0.5 ml Luer-Lock syringe system coupled with a FluroTec® plunger. The Daikyo Crystal Zenith® syringe is composed of a cyclic olefin polymer (COP) – having a very low surface energy. The FluroTec® plunger is laminated with a fluorpolymer film. The plunger moves easily and consistently in the syringe (minimal friction between fluoropolymer and COP) – without the use of silicone oil. The Daikyo Crystal Zenith® syringe is the only silicone-oil-free system with this key additional benefit – the fluoropolymer film protects the drug product from potential interaction with the elastomer comprising the plunger – reducing risk of leachables from plunger, and reducing risk of absorption of drug product by plunger.
Daikyo Crystal Zenith® is a registered trademark of Daikyo Seiko, Ltd.
Daikyo Crystal Zenith and FluroTec technologies are licensed from Daikyo Seiko, Ltd.