Stability testing products

The moisture content of a plastic affects such conditions as electrical insulation resistance, dielectric losses, mechanical properties, dimensions, and appearances. The effect on the properties due to moisture content depends largely on the type of exposure (by immersion in water or by exposure to high humidity), the shape of the product, and the inherent behavior properties of the plastic material. The ultimate proof for tolerance of moisture in a product has to be a product test under extreme conditions of usage in which critical dimensions and needed properties are verified. Plastics with very low water-moisture absorption rates tend to have better dimensional stability. 

Two types of laboratory tests were conducted to evaluate contaminant tests, a catalyst stability test and a high-conversion bromine product test. For catalyst stability testing, only a small amount of catalyst was used (1.5 g) to ensure incomplete conversion of the HBr. If a feed contaminant causes catalyst deactivation, it is apparent as an immediate decrease in conversion. If an excess of catalyst was used instead, even if deactivation occurred at the inlet of the bed, it may not be detected until the region of deactivation moves considerably downstream. This could take many hours or days. 

The purpose of stability testing is to assess the effects of temperature, humidity, light, and other environmental factors on the quality of a drug substance or product. The data produced are used to establish storage conditions, retest periods, shelf loss, and to justify overages included in products for stability reasons. The most useful equation relating temperature and reaction rate is the Arrhenius equation. This equation (27) may be integrated and rewritten as Eqs. (31) and (32). 

Formulation development, production, and stability testing of clinical dosage form... 

Guidance on Nonclinical Safety Studies for the Conduct of Human Clinical Trials for Pharmaceuticals Notice Stability testing of new drug substances and products Stability testing Stability testing... 

Stability tests on finished dosage forms and products Tests for conformance to pharmacopeial standards Exploratory studies on viruses and cell biology Tests of functionality and/or appropriateness of food additives... 

Biobatch manufacturing Inspection to determine the establishment s compliance with cGMP requirements, including a data audit of the specific batches on which the application is based (e.g., pivotal clinical, bioavailability, bioequivalence, and stability) is a field office responsibility. CDER scientists are responsible for the review and evaluation of the records and data submitted in the application, including the components, composition, batch instructions, in-process and finished product test points, and... 

Finished Product Test Data Stability Reports Process Validation Report... 

Application/compendial release requirements and stability testing Stability first production batch long-term data in annual report... 

Matsuo M, Machida Y, Furuichi H, Nakamura K, Takeda Y. Suitability of photon sources for photostability testing of pharmaceutical products. Drug Stability 1996 1 179-187. 

Sampling batches from production for stability evaluation Sampling units from batches for stability studies Sampling units from stability study for testing Sampling analytical samples from units selected for testing Number of units... 

Preventative Action. This observation could have been avoided by establishing a stability testing program SOP that specifies batches that are to be entered into the annual stability program, including all container-closure systems, and that requires that all commercial container-closure systems be tested. The stability program must include an evaluation of degradants and impurities if it is intended to assess stability. Additionally, a product-specific stability protocol should have been developed that specified the methods to be used. 

Changes should also be correlated with the statistical data available from stability, inprocess, and finished-product testing. The statistical data should be examined for trends in specification test results. Where trends are found (e.g., increases or decreases in potency, decreases in stability) the change control records should be evaluated to determine whether or not changes have occurred that might be responsible for the shifts in QC trends and analytical results. 

The catalyst samples from both experiments were then analyzed by a variety of techniques described below. Portions of each catalyst sample [ 5g) were loaded into one of four laboratory micro reactors operated under identical experimental conditions. The catalysts were kept on line until the activity, as measured by the daily drainage of water and hydrocarbon products, had stabilized. The activity was determined as a function of water produced under these steady state conditions. Each of the laboratory micro reactors was tested with a known catalyst standard to establish both the data reproducibility and possible effects of the different reactors on the activity measurements. The different reactors gave results with relative differences of less than 3%. 

A stability test is made after 2 hours drying at 100 °C hi order to ascertain the drop in active chlorine content. A stable product manufactured in Moore s equipment shows a loss of 3.5 per cent while an unstable product about 14 per cent. From this we can see that although decomposition is suppressed to a considerable extent in the case of a stable product, the active chlorine loss is still noticeable. The so called superstable bleaching powder is prepared by the addition of quick lime to the stable product. A stability test then shows active chlorine loss to be less than 0.75 per cent. 

This test, which lasts 64 days and is described in Dutch standard NEN 7345, is intended to determine leaching from products or stabilized waste materials as a function of time. The product is immersed in acidified demineralized water. This eluate is refreshed at seven specified times. Analysis of the eluates enables the leaching per square meter of product surface area and the effective diffusion coefficient to be calculated. 

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