Tablet testing accelerated

Changes in physicochemical properties of the drug substance (e.g., color, crystal modification) may take place upon irradiation. Efforts should be made to observe such changes during the in vitro assay. The sample absorption spectrum should be recorded before and after irradiation surface color of solid samples should be evaluated by appropriate methods and the identity of the sample crystal modification should be confirmed when the drug is irradiated in the solid state. The humidity in the test chamber can influence the photochemical stability of certain solid samples, as demonstrated for mefloquine. The photoinduced yellowing of uncoated mefloquine tablets is accelerated by an increase in humidity. These tablets are mainly used in tropical countries and the real in-use conditions will include high relative humidity. In such cases, the influence of the humidity on the photostability must be taken into account (Tpnnesen et al., 1997). 

The appearance of tablets and powders during accelerated stability testing can be quantified using tristimulus colorimetry [29]. In this work, various formulations were stored under stress conditions, and the tristimulus parameters... 

Amidon, G. L., and Middleton, K. R., (1988), Accelerated physical stabihty testing and long-term predictions of changes in the crushing strength of tablets stored in bhster packages, Int. J. Pharm., 45, 79-89. 

Carstensen JT, Johnson JB, Valentine W, Vance JJ. Extrapolation of appear-ence of tablets and Powders from Accelerated Storage Tests. J Pharm Sci 1964 53(9) 1050-1054. 

Tardif R. Reliability of accelerated storage tests to predict stability of vitalimes (A, Bl, C) in tablets. J Pharm Sci 1965 54 281-284. 

If the solution or the filtrate from Group IIIB is brown or dark in colour, Ni may be suspected. The dark-coloured solution contains colloidal NiS, which runs through the filter paper. It may be acidified with acetic acid, and then boiled until the NiS has coagulated this may either be added to the Group IIIB precipitate or tested separately for Ni. As a general rule, the addition of macerated filter paper (e.g. in the form of a portion of a Whatman filtration accelerator or ashless tablet) to the suspension before filtration will lead to a clear or colourless solution. 

A penetrating dye-solution test was used in order to determine whether the foil packages permitted any transmission of moisture. High humidity accelerated the physical deterioration of effervescent tablets when stored in packets of poor integrity. ... 

Davies PN, Storey DE, Worthington HEC. Some pitfalls in accelerated stability testing with tablet and capsule lubricants. /... 

A compaction simulator must be able to mimic the full compression cycle of the unit operation. Early attempts at compaction simulation utilized mechanical property testing equipment (e.g., Instron and Lloyd type machines) to compact powders into compacts. Although these machines were well suited to apply appropriate compression loads, they were not designed for the high velocities and accelerations necessary to simulate the double-ended compression cycle of a rotary tablet press (2). 

The ehoiee of excipients impacts the physical properties of the tablet. They can accelerate or retard tablet disintegration, affect the hardness of the tablet, or impact the stability of the dosage form by adsorbing moisture from the atmosphere. Careful selection and testing of excipients is therefore of paramount importance. 

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