Standard for gibberellic acid (gibberellin A3) active constituent
Version 1 August 2004
1. Description: the material shall consist of gibberellic acid together with related manufacturing impurities and shall be a crystalline solid, free from visible extraneous matter and added modifying agents.
2. Common Name: gibberellic acid (gibberellin A3)
3. Chemical Name (IUPAC): (3S,3aS,4S,4aS,7S,9aR,9bR,12S)-7,12-dihydroxy-3-methyl-6-methylene-2-oxoperhydro-4a,7-methano-9b,3-propeno[1,2-b]furan-4-carboxylic acid
4. CAS Number: 77-06-5
5. Identity test: identity of the active constituent must be established by one or more of the following methods: spectroscopic tests (IR spectrum, NMR, mass spectra), Chromatography (HPLC or GC retention time with reference compound) or any other suitable test method.
6.1 Active constituent: 850 g/kg minimum
7. Analytical methods
- The analytical method used for the determination of the active constituent and toxicological significant impurities must be validated in accordance with the APVMA guidelines for the validation of analytical methods.
- The APVMA guidelines on validation of analytical methods state that “Analytical methods described in CIPAC handbooks and AOAC International Manual, and in recognized pharmacopoeias [BP, BP (Vet), Ph Eur and USP] for a particular active constituent or formulation are regarded as validated and do not require revalidation. However, the suitability of these methods must be verified under actual conditions of use i.e., the selectivity and accuracy of the method should be demonstrated for the published method when applied to the relevant sample matrix and laboratory conditions.
- When a CIPAC or AOAC method is used for the assay of an active constituent in a bulk active constituent, there is no matrix. The registrants need to check the specificity of the method to ensure there is no interference from impurities or degradation products. However, determination of accuracy of the method is not required as there is no matrix effect. However, when a CIPAC or AOAC method is used for the assay of an active constituent in a formulated product, determination of both specificity and accuracy is required as the matrix is relevant in formulated products (formulated products have different composition and quantities of excipients).
- Refer to Guidelines for the Validation of Analytical Methods for Active Constituent, Agricultural And Veterinary Chemical Products (PDF, 164kb).
- Unless the scope of the collaborative method (CIPAC and AOAC) also includes toxicological significant impurities in the active constituent, validation data for impurities are required.
Association of Official Analytical Chemists (The Official Methods of
CIPAC: Collaborative International Pesticides Analytical Council