Stability testing test attributes, procedures

Test attributes procedures and acceptance criteria selection of batches testing frequency storage containers, conditions, and period, as well as data evaluation are discussed in great detail. Data evaluation considers out-of-specification results. Documentation covers protocols and protocol amendments, deviation reports, out-of-specification reports, test results and raw data, and stability reports. 

Where such reprocessing occurs, written process change procedures should be approved by the quality control unit that clearly specify the conditions and limitations of repeating chemical reactions. In addition, the procedures should establish how this type of reprocessing will be evaluated, and what additional tests will be conducted on the reprocessed material to show that the resulting material is of a purity and quality comparable to that normally produced by the process. These tests should include, as appropriate, purity, impurity profiles, stability testing on initial reprocessed tots, and testing for physical attributes. 

Physical testing encompasses a wide range of techniques, from visual examination to spectroscopy. It is often the physical attributes which the patient or practitioner can evaluate prior to administration. For example, a particle found in a parenteral formulation can foretell the presence of a new chemical degradant found during stability studies. Many of the procedures in this chapter are performed routinely as part of release or stability testing of API or pharmaceutical products. 

The primary objective of method validation is to provide a high degree of assurance that the specified method consistently provides accurate test results that evaluate a product against its defined specification and quality attributes (Chapter 12). The regulations require that validation data be available to establish that the analytical procedures used in testing meet proper standards of accuracy and reliability. All analytical procedures require some form of validation, regardless of whether the method is used for stability, in-process analysis, release, or acceptance. Most of the discussions focus on the validation of HPLC methods using assay and purity determinations nevertheless, fundamentals of the approach can be applied to most method validation activities. 

Fe(III)-cyanide species that according to the literature [10-12] absorbs in the IR above 2100 cm . However, we were not able to detect any traces of Fe either in the filtrate after the exchange procedure or in the FeY zeolite (SCN test). Even when the synthesis is carried out in an air atmosphere, no traces of Fe are detectable, due to the high stability of Fe(NH4)2(SO4)2 employed as the source of Fe(II) ions. Therefore, it is reasonable to attribute the second band at -2115 cm to the presence of other Fe(CN)x species but in different environments. Moreover this species seems to... 

The hnished product will be subjected to inspection and rigorous testing for identity, uniformity, residual water content, stability, sterility and potency. In addition, all analytical techniques employed in testing these attributes will themselves have been subjected for reliability, reproducibility, experimental uncertainty limits. The biotechnological revolution has resulted in the appearance of ever more rehned and sensitive analytical techniques, mainly novel types of spectroscopy and coupled techniques, based on mass spectrometry, known usually by complex acronyms, e.g. MALDI-TOE-MS (Matrix-Assisted-Laser-Z)esorption-71me-of-Tlight-Mass Spectrometry). Some of the available analytical procedures are treated in more detail in the next chapter. 

The information and examples presented above demonstrate how compendial procedures and general chapters may be applied for determining the strength, identity, quality, and purity of products on stability. It is up to the users to understand which product attributes are critical for stability and then couple the appropriate compendial test to measure those attributes. 

To ensure that the experimental procedure adopted results in the highest-possible colloidal nanoparticle concentration, the sequence of precursor addition was reversed. A second scheme which involved mixing the metal salt powder with microemulsions already containing the stoichiometric amount of NaOH solution was tested. Both schemes succeeded in forming stabilized colloidal nanoparticles however, higher uptake was obtained when scheme 1, solubUizing the metal salt before adding NaOH, was employed. The lower uptake associated with scheme 2 was attributed to the formation of a mass transfer barrier of the metal oxide/hydroxide at the surface of the salt powder, which prevented further dissolution. 

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