PT - JOURNAL ARTICLE AU - Shi, Galen H. AU - Shinkle, Sharon L. AU - Gopalrathnam, Ganapathy AU - Dong, Xia AU - Hofer, Jeffrey D. AU - Jensen, Eric C. AU - Rajagopalan, Natarajan TI - Impact of Formulation Variables on Silicone Oil Distribution and Functionality of Prefilled Syringe System AID - 10.5731/pdajpst.2017.008169 DP - 2017 Jan 01 TA - PDA Journal of Pharmaceutical Science and Technology PG - pdajpst.2017.008169 4099 - http://journal.pda.org/content/early/2017/10/10/pdajpst.2017.008169.short 4100 - http://journal.pda.org/content/early/2017/10/10/pdajpst.2017.008169.full AB - The interior surface of prefilled syringes is typically coated with silicone oil for lubrication to aid in free plunger movement. This article discusses the impact and interaction of formulation variables with silicone oil within the interior surface of the barrel. Characterization techniques including syringe glide force, break loose force, ZebraSci imaging, contact angle, ICP, and RapID were used in assessing the interactions. Data indicate formulation variables of pH, buffer and tonicity agent type and concentration and surfactant can impact silicone oil distribution of prefilled syringes leading to changes in functional properties of the syringe over time. Syringe samples containing acetate and histidine buffers showed an increase in glide force at accelerated temperature conditions, but the change was minimal at 5°C. The samples with the highest glide force correlate with the presence of sodium acetate buffer in combination with mannitol. Sodium chloride appeared to have lesser impact on glide force than mannitol. Samples with higher glide force appeared to exhibit a change in the silicone oil layer of the syringe, as observed with ZebraSci imaging, as well as significant reduction in surface hydrophobicity, as demonstrated through contact angle measurement. These data indicate the morphology of the siliconized surface may be changing over time in contact with different formulation variables.