DIN EN ISO 10993-18
Biological evaluation of medical devices - Part 18: Chemical characterisation of materials
The new version of DIN EN ISO 10993-18 was published this month and replaces the version from August 2009.
The standard DIN EN ISO 10993-18 describes a method for identifying and, if necessary, quantifying the components of a medical device. This procedure enables the identification of biological hazards and the assessment and control of biological risks posed by component materials.
A largely step-by-step approach to chemical characterisation is described, which may include one or more of the following steps.
Chemical characterisation
- Identification of the manufacturing materials (specifications),
- Characterisation of the manufacturing materials by identifying and quantifying their chemical constituents (material composition),
- Characterisation of the medical device with regard to chemical substances introduced during manufacturing (e.g. mould release agents, manufacturing-related impurities, sterilisation residues),
- Estimation (under laboratory extraction conditions) of the potential of the medical device or its manufacturing materials to release chemical substances under clinical conditions of use (extractable substances),
- Measurement of the released chemical substances within the scope of the intended purpose (extractable substances).
The DIN EN ISO 10993-n series of standards applies when the medical device comes into direct or indirect physical contact. DIN EN ISO 10993-1 can be used for the precise categorisation of contact situations and verification.
Listing Amendments
Compared to the August 2009 version, the following changes have been made to DIN EN ISO 10993-18:
- Better harmonisation with other parts of the DIN EN ISO 10993-n series of standards,
- A revised and expanded flow chart for the chemical characterisation process has been added,
- an improved explanation of the circumstances under which analytical tests can be dispensed with,
- a number of definitions have been added (e.g. configuration of the medical device, manufacturing materials, material composition),
- test approaches for material characterisation are explained in more detail,
- a discussion of considerations for analytical method qualification has been added,
- informative appendices on general principles and considerations have been added.
In complex regulatory practice, chemical characterisation is also playing an increasingly important role in the low and medium risk area (Class I and IIa). Manufacturers who in the past were satisfied with cytotoxicity testing, for example, should urgently consider this part of the series of standards. Of course, our team of experts with many years of expertise is also at your side here.