Standard Practice for Extraction of Materials Used in Medical Devices

Importancia y uso:

5.1 These extraction procedures are the initial part of several test procedures used in the biocompatibility screening of plastics or other materials used in medical devices.

5.2 The limitations of the results obtained from this practice should be recognized. The choices of the extraction vehicle, duration of immersion, and temperature of the test are necessarily arbitrary. The specification of these conditions provides a basis for standardization and serves as a guide to investigators wishing to compare the relative resistance of various plastics or other materials to extraction vehicles.

5.3 Correlation of test results with the actual performance or serviceability of materials is necessarily dependent upon the similarity between the testing and end-use conditions (see 12.1.2 and Note 7).

5.4 Caution should be exercised in the understanding and intent of this practice as follows:

5.4.1 No allowance or distinction is made for variables such as end-use application and duration of use. Decisions on selection of tests to be done should be made based on Practice F748.

5.4.2 This practice was originally designed for use with nonporous, solid materials. Its application for other materials, such as those that are porous, absorptive (for example, sponge-like materials that are capable of absorbing liquid), or resorptive, should be considered with caution. Consideration should be given to altering the specified material-to-liquid ratio to allow additional liquid to fully hydrate the material and additional liquid or other methods to fully submerge the test specimen. Additional procedures that fully remove the extract liquid from the test specimen, such as pressure or physically squeezing the material, should also be considered as appropriate. Although no definitions are given in this practice for the following terms, such items as extraction vehicle surface tension at the specified extraction condition and test specimen physical structure should be taken into account.

Note 1: While there are no standardized methods available at present for determining the solvent absorption capacity of an absorptive device or material, a suggested protocol is as follows:
– Determine the volume of extraction vehicle that each 0.1 g or 1.0 cm² of device/material absorbs;
– then, in performing the extraction, add this additional volume to each 0.1 g or 1.0 cm² in an extraction mixture.

5.5 Test Methods D570 and D1239 and Practices D543 may be useful in providing supplemental information.

Subcomité:

F04.16

Referida por:

F2064-17, F3127-22, F2565-21, F0451-21, F0750-20, F2027-25, F0648-21, F2103-18, F0748-25, F0756-17R25, F2347-24, F2147-01R25, F2148-18, F0749-20, F0720-24, F2695-12R25, F3321-25, F2759-19, F0719-20R25, F1903-18, E3219-25, F1904-23, F0561-19

Volúmen:

13.01

Número ICS:

11.100.99 (Other standards related to laboratory medicine), 83.080.01 (Plastics in general)

Palabras clave:

biocompatibility; extraction; liquids; material; medical device; plastics; specimen size;