- Insight
Focus and outcome of this study
The study reveals noteworthy results that affirm the need for drug manufacturers to adopt post-cured tubing as standard. This paper details that samples of WMFTG Pumpsil tubing (post-cured and non post-cured) were extracted with a 50% ethanol: 50% water solution for 30 minutes at 25C and seven days at 40C.
For the purposes of this paper, the extractables studied were the cyclosiloxanes (mixtures of cyclosiloxanes have been of particular interest due to concerns about their potential toxicity).
The extracts were analysed by Gas Chromatography – Mass Spectrometry (GCMS). The study demonstrated the presence of cyclosiloxanes was reduced by a minimum of 25% in the post-cured extracts, as compared with non post-cured extracts over a seven day extraction period and by 50% over a 30 minute time point.
Introduction
Tubing has been a part of biopharmaceutical manufacturing processes for many years. Even in the early days of the biopharmaceutical industry, tubing was used for fluid transfer, peristaltic pumping and filling operations.
The advent of single-use technologies has increased the usage of tubing from being a minor player within the manufacturing process, to become a major part of single-use biopharmaceutical manufacturing assemblies, used to link the different technologies such as filters, connectors and biocontainers together. Silicone tubing comprises of polydimethylsiloxanes (PDMS) polymers. Silicone tubing can be divided into two cross-linking types, those manufactured by addition (platinum) and free radical (peroxide) curing systems.
The peroxide-cured silicone tubing has fallen out of favour in recent years due to concerns about the presence of 2-4 dichlorobenzoyl acid as a by-product which has the potential to leach into contacting fluids. Addition cure has no by-products, and as a result the biopharmaceutical industry has transitioned to mostly using platinum-cured tubing.