Understanding the subtle difference between extractables and leachables is important when selecting sample storage tubes. Both can be present in inferior products due to poor manufacturing techniques, but more importantly they can be avoided entirely.
Extractables are chemical species or compounds that can be extracted from a primary container or its components, such as elastomeric or plastic material. They can contaminate drug or biological products, impacting its quality. Extractables are mostly generated by interaction between products and their packaging over time, usually under extreme conditions, such as the presence of strong solvents or elevated temperatures. Extractables can also be caused by gamma irradiation1.
Leachables are compounds that leach into the drug or biological product from the container-closure system, such as the elastomeric or plastic components, or coatings of the container and closure system. Leaching is mainly a result of direct contact with the formulation under normal conditions of use. Leachables are typically a subset of extractables and have potential to affect the product in various ways1. Leachables can be present due to additives or steps during the manufacturing process, including the addition of release agents and coatings.
These distinctions can create a little-known dilemma for researchers. Leachables and extractables can be present in sample storage consumables manufactured using either:
Leachables could always be present in an inferior quality sample storage tube, whereas extractables may only be present after gamma irradiation to sterilize tubes produced in a non-sterile environment.
Don’t risk your sample integrity. Your sample may be in direct contact with the polypropylene resin of the tube for more than 10 years, and any leachables can have an impact on the quality of your sample. In independent testing, Azenta Life Sciences tubes were the only sample tubes tested to consistently show no leachables or extractables.
1. N. P. Shah, N. M. Patel, P. K. Patel, (2013) Impact of Steam and Gamma Processing on Extractable, International Journal for Scientific Research & Development.