Exaggerated Extraction of Medical Devices
An exaggerated extraction study on a medical device is a forced extraction study to generate a complete extractable profile for hazard identification and is required by ISO 10993-12 to be exhaustive. An overview of the exaggerated extraction study can be found below. The key decision in study design is solvent selection. For an exaggerated extraction study, the extraction solvents are selected based upon the anticipated tissues the device will encounter. The extraction type is based on the solvent type and the analytical methods for analysis of extractables are the same for all extractions. For exaggerated extractions, the extraction must be proven to be exhaustive, therefore extraction time is established experimentally. Extractables are identified by MS and quantitated against structurally similar standards.
Overview of Exaggerated Extraction Study for Medical Devices
Solvent Extraction Type Analytical Methods 1. Polar – water, phosphate buffered saline, culture media without serum
2. Non-polar – ethanol/water, ethanol/saline, dimethyl-sulfoxide.
1. Low boiling neat solvents : Soxhlett
2. Mixed solvents, buffers and high boiling neat solvents: Batch extraction with agitation or circulation
1. Volatile organic extractables by GC-MS
2. Non-volatile organic extractables by LC-MS
3. Inorganic extractables by ICP-MS (aqueous extract only)