Solid dosage forms components

Primary container-closure system-related data will need to cover storage, transportation, and use. The choice of materials of construction, their description, and the ability of the container-closure system to protect from moisture and/or light will need to be considered. The compatibility of the container-closure and its contents will need to consider sorption, leaching, and safety. The performance of the container-closure system will also need to be considered in terms of dose delivery from any associated device that is to be supplied as part of the product. Container-closure components will require adequate specifications covering description, identification, critical dimensional tolerances, and test methodology (including pharma-copeial and noncompendial methods). More data are likely to be required for liquid or semi-liquid products than for solid dosage forms. In the latter, product stability data and container-closure system specifications may suffice. 

This need is addressed in part by NIR-CI, in that it offers the ability to obtain high fidelity, spatially resolved pictures of the chemistry of the sample. The ability to visualize and assess the compositional heterogeneity and structure of the end product is invaluable for both the development and manufacture of solid dosage forms. NIR chemical images can be used to determine content uniformity, particle sizes and distributions of all the sample components, polymorph distributions, moisture content and location, contaminations, coating and layer thickness, and a host of other structural details. "... 

Another example of an excipient-excipient interaction that can be used to our advantage is the one between xanthan gum and locust bean gum (carob gum or cer-atonia) in the presence of water. This interaction forms the basis of the identification test for Xanthan Gum NF. The interaction creates a much more viscous gel system than can be created using either component alone. This has been used in the formulation of controlled release oral solid dosage forms in the TimeRx drug delivery system (11). 

Disintegration tests allow for precise measurement of the formation of fragments, granules, or aggregates from solid dosage forms, but do not provide information on the dissolution rate of the active drug. The disintegration test serves as a component in the overall quality control of tablet manufacture. 

Pharmaceutical Excipients are components of finished drug products and site active components are recognized in the USP/NF. A list of key excipients for solid dosage forms is given ... 

Many examples of the effects of tablet excipients on dmg decompositions are reported in the pharmaceutical literature. Chemical interaction between components in solid dosage forms may lead to increased decomposition. Replacement of the phenacetin in compound codeine and ARC tablets by paracetamol in NHS formulations in Australia in the 1960s (because of the undesirable side-effects of phenacetin), led to an unexpected decreased stability of the tablets. The cause was later attributed to a transacetylation reaction between aspirin and paracetamol and also a possible direct hydrolysis of the paracetamol (Scheme 4.15). 

Because of its vinyl acetate component, copovidone is somewhat more hydrophobic and gives less brittle films. This gives the product its favourable properties as a soluble binder and film-forming agent, particularly for solid dosage forms. 

Specificity is the ability to assess unequivocally the analyte in the presence of components that may be expected to be present. A major problem with utilizing NIR to accurately determine concentrations of actives in solid dosage forms is that... 

---