Becton, Dickinson and Company
Syringe Plunger Stopper for High Dose Accuracy Drug Delivery

Abstract:

A plunger stopper (12) configured for attachment with a plunger rod (14) for use with a within a syringe barrel for high dose accuracy drug delivery. The stopper having a first portion (40) formed from a first material and a second portion (42) formed from a second material, wherein the second material has a greater rigidity than the first material and wherein the second portion is configured to be attached to a plunger rod. The second material can be in the form of an insert (44) which functions to reduce the amount of distortion of the stopper during use, reduce air bubble size variation from fill to fill, maintain a seal with the inner wall of the syringe barrel with lower contact pressure in a resting state and reduce the amount of hysteresis of the stopper. The stopper can be adapted for use with infusers, pens, and other types of auto-injectors.