You are here

Guidelines for sterility testing of therapeutic goods

13 September 2006

Book pagination

7. Diluents, solvents and wash  solutions for use in sterility testing

700. Relevant sections of the BP/Ph Eur: 'Test for sterility of the product to be examined'; 'Application of the test to parenteral preparations, ophthalmic and other non- injectable preparations required to comply with the test for sterility'.


701. The composition of the diluents referred to in Table 4 (Diluents 1, 2 and 3) are specified in Annex III.

702. These diluents may be modified by addition of antimicrobial inactivators or other equally or more effective diluents may be used, if indicated by validation studies.

Method of preparation

703. Diluents, solvents and wash solutions should be prepared according to written procedures that are based on a validated sterilisation process.

704. Every batch should be assigned a unique batch number and expiry date and its manufacture documented.

705. Detailed guidance for preparation of the diluents listed in Table 4 is provided in Annex III.

Tests on diluents, solvents and wash solutions

706. Diluents, solvents and wash solutions should be tested before use for pH and where practicable, for sterility.

707. Measure the pH of a sample of each batch. Any batch whose pH is not within the range specified in Annex III for that diluent should not be used in tests for sterility.

708. To check for sterility, incubate the preparation at 30 - 35°C and 20 - 25°C for 14 days. This testing may be performed on 100% of the batch or on representative portions and may be conducted concurrently with the product sterility test. Solutions that are turbid, or which contain visible particulate matter, should not be used in tests for sterility. Parametric release of diluents and solvents may be permitted by the competent authority (see also clause 610).


709. Diluent 3 which is more than 10 days old should not be used in tests for sterility.

Book pagination