Stability studies conditions

The stability study conditions recommended by ICH guidelines are as follows ... 

Stability studies under anhydrous conditions were also conducted using the aliphatic-aromatic homopolyanhydrides. These polymers were completely stable in the solid state in vacuo for over 6 months at 25°C (8). 

REDDY SASTRY c V, RUKMINI c (1997) Stability studies on stabilized rice bran under accelerated conditions for twelve weeks. (RiceX Company Report). 

G. M. Graham, M. M. Jordan, K. S. Sorbie, J. Bunney, G. C. Graham, W. SableroUe, and P. HiU. The implication of HP/HT (high pressure/high temperature) reservoir conditions on the selection and application of conventional scale inhibitors Thermal stability studies. In Proceedings Volume, pages 627-640. SPE Oilfield Chem Int Symp (Houston, TX, 2/18-2/21), 1997. 

NoV are readily transferred from hands to fomites and vice versa (Bidawid et al., 2004 D Souza et al., 2006). The pronoimced environmental stability of NoV particles also contributes to the spread of outbreaks from point sources of surface contamination. All stability studies have made use of surrogate organisms to model NoV response to conditions, since the human virus is not easily grown in cell culture (Duizer et al., 2004b Straub et al., 2007). The murine norovirus (MNV) and the feline calicivirus (FCV) have both been used, with the mouse virus providing more... 

In many cases, there is difficulty in preserving residues in samples after collection and prior to pesticide analysis which coincides with a rapid further degradation and mineralization of the pesticide residues under most environmental conditions. Storage stability studies and studies on the reactivity of sample collection equipment in addition to field quality assurance procedures can help address some of these questions. Concerns are accentuated for compounds that have short half-lives in the environment but still have high acute toxicity. 

The degradation of agrochemicals during storage may result from a variety of factors such as acidic and alkaline hydrolysis, enzymatic action, etc. It is recommended that a preliminary stability study be performed for the chemical in the environmental sample. If the chemical is stable under acidic conditions, for example, samples can be stored after acidification with hydrochloric or phosphoric acid. 

Dwivedi et al. used a thin-layer chromatographic densitometric and ultraviolet spectrophotometric methods for the simultaneous determination of primaquine and a new antimalarial agent, CDRI compound number 80/53 [68]. The new antimalari-al agent, compound 80/53 is unstable in acidic conditions where it is converted into primaquine. To conduct stability studies of this compound, thin-layer chromatography densitometric and ultraviolet spectrophotometric determination methods were developed. These methods are also suitable of the determination of compound 80/53 or primaquine in bulk and pharmaceutical dosage forms. 

Stability of the test chemical in drinking water under study conditions should be determined prior to study initiation. Consideration should be given to conducting stability tests on test chemical-drinking water admixtures presented to some test animals. Besides difficulties of inherent stability, changes in chemical concentrations may result from other influences. Chemicals with low vapor pressure can volatilize from the water into the air space located above the water of an inverted water bottle thus, a majority of the chemical may be found in the dead space, not in the water. 

For those scientists who had to perform quantitation, the linearity of the A/D was also critical. Linearity is the condition in which the detector s response is directly proportional to the concentration or amount of a component over a specified range of component concentrations or amounts. It is imperative that the A/D not add any additional error or variability to the performance of the detector. The resulting calibration curve now becomes dependent on the combined linearity of the detector and the /VD. Accurate quantitation requires that the system is linear over the range of actual sample concentrations or amounts. Many pharmaceutical assays, like degradation and stability studies, require that the system be able to identify and quantitate very disparate levels of peaks. In many cases, this translates into a 3 to 4 order of magnitude difference between the main active component and the impurities that need to be quantitated. 

It has been predicted that a Pd skin on a PdsFe core would sit close to the top of the activity/O binding energy "volcano" curve and thus have significantly higher activity than Pt and Pt/Pd core-shell materials. If these materials could be shown to be stable to long-term PEM conditions, then these could represent viable replacements for Pt. As with other alternative non-Pt catalysts, very few stability studies have been reported. 

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