ISO 10993 Lab Report

Introduction:
This part of ISO 10993 details sample preparation methods and gives requirements and guidance foe the selection of reference materials for the biological evaluation of medical devices.
The methods of sample preparation should be appropriate for the biological evaluation and materials to be evaluated.
The biological test method requires the extraction solvents, selection of materials and conditions.

Scope:
This part of ISO 10993 focuses on the following:
Selection of test sample
Selection of representative portions from a device
Preparation of test sample
Experimental control
Selection and requirements, for reference materials
Extract preparation

General requirements:
While designing and preparing the test samples as described

Reference materials are certified by the suppliers. For a specific test/procedure the individual laboratories should identify the biological characterization that is necessary to qualify a reference material.

Use of reference materials as experimental control:
To demonstrate the adequacy of a procedure to produce reproducible response reference materials are used as control materials in biological tests.
Reference material when used as experimental control should be in the same class of material as that of test sample (i.e. polymer, ceramic, metal, etc.)

Test sample selection:
The choice of test sample should be justified and the testing can be done on final product, materials processed or representative samples of the final product and/or any extracts of these.
When an extract is to be tested similar procedure is applied to the sample selection.

Test sample and reference material

To enhance the submersion in extraction media, the materials are cut into small pieces. For example- polymers are cut into pieces of 10mm x 50mm or 5mm x 25mm.
Extraction should be performed by using both polar (water) and non-polar (cottonseed or sesame oil) vehicles. Ethanol/water, ethanol/saline etc. can also be used as extraction vehicles.
Extraction should be carried out with agitation under statistical conditions.
The stability and homogeneity of extract should be considered if it is stored for more than 24 hours.
The pH of the extract should not be adjusted unless a rationale is given.
When hazards of polymeric devices are to be identified exhaustive extraction should be followed.
The devices through which fluids are circulated; extraction by re-circulation under normal conditions should be carried out.
Extraction conditions for hazard identification and risk estimation in the