Chemical Characterization of Medical Devices

Extractables - Chemical Potential
Extractables are chemical compounds that can migrate from a material when exposed to exaggerated laboratory conditions such as strong solvents, elevated temperatures or extended extraction times. These studies establish the potential chemical profile of a material and identify compounds that could become leachables.

Extractables testing intentionally creates worst-case conditions to:

• Identify and quantify compounds that could potentially migrate from a device or material
• Establish a comprehensive chemical profile of the material
• Detect compounds that may later appear as leachables under real-world use

Because the conditions are intentionally aggressive, extractables studies typically identify more compounds than would migrate during normal clinical use.
 

Leachables - Acutal Exposure

Leachables are chemical compounds that actually migrate from a material or medical device into a drug product or contacting medium under normal storage or clinical use conditions.

Leachables studies evaluate realistic patient exposure by using simulated-use conditions, such as representative solvents, physiological media, or product matrices.

These studies:

• Identify compounds that migrate during actual or simulated use conditions
• Quantify potential patient exposure
• Confirm whether compounds detected in extractables studies appear under real-world conditions
   

When combined with a toxicological risk assessment (TRA), extractables and leachables studies help determine whether additional biological or safety testing is necessary.