Spalling and sorption of tubing for peristaltic pumps.

Available tubing for peristaltic pumps tend to shed particulates into the solution due to their poor abrasion characteristics. Most commonly used flexible tubing is silicone rubber or polyvinyl chloride (Tygon) tubing. Two newly available tubing are manufactured from a composite of expanded polytetrafluoroethylene (Teflon PTFE) with platinum-cured silicone rubber (Sta-Pure) and a tubing composite of PTFE with fluoroelastomer (Chem-Sure). These are claimed to resist spalling and deliver constant volume when used in peristaltic pumps. The four tubing were compared for spallation. They were also compared for sorption of methylparaben, propylparaben, and benzyl alcohol over a 72 hr study. Spallation studies indicate that Tygon and silicone tubing are prone to damage and shedding of particulates due to abrasion during use in peristaltic pumps while the Chem-Sure and Sta-Pure tubing are resistant to abrasion and spalling and show negligible shedding of particulates over 72 hr use in the peristaltic pump. Chem-Sure shows no spalling after 48 hr. Decrease in volume delivered is expected using Tygon and silicone tubing only. Chem-Sure tubing did not show any preservative losses. Tygon sorbed all preservatives tested to the greatest extent, followed by Silastic and Sta-Pure tubing, in decreasing order of sorption. Propylparaben was sorbed to the greatest extent. The tubing used appear to approach saturation in 24-48 hr. Chem-Sure and Sta-Pure tubing are ideal for use in peristaltic pumps or for general use for any demanding pharmaceutical applications.