Tablet processing control unit

The product of the simpler synthesis was compared in detail with the product of the RR-amine process. In particular, the Research Quality Control Unit searched for the presence of different polymorphs and new impurities (e.g., the dialkylation byproduct from the first step). They compared the stabilities of both products and also compared the hardness and dissolution rates of tablets made from both products. Since the DBTA resolution, crystallization, and product isolation steps, as wll as the final dilevalol hydrochloride preparation step, were the same for both the RR-amine process and the simpler synthesis, it was anticipated that these steps should protect against the introduction of new impurities or changed physical parameters in the final crystalline product. Such proved to be the case. 

In a setup-dominant process, it is important that the development function understand where the setup must be centered (targeted). This information is most useful when instruments can effectively and accurately measure the property of the intermediate material (e.g., powder blend) or dosage unit. This capability is reinforced whenever an instrument reading outside the given specifications causes an equipment response (e.g., activation of a servo motor on a tablet press). Caution limits within the normal product limits are established purposefully to effect this kind of control. 

Many tablet medications intended for unit dose applications are protected by the familiar blister packs, an example of which is shown in Figure 10-26. These are typically manufactured with laminated materials that consist of a transparent polymer, an aluminum foil, and an interfacial adhesive. There are many variations of this construction. The transparent polymer layer is first dimpled with a heated die to produce the tablet cavities. The web material, consisting of the aluminum foil and adhesive, is thermally bonded under pressure to the perimeter of the cavities after the tablet is inserted. This is a continuous process in which the line speed, compression force, and temperature must be controlled to assure a hermetically sealed package. 

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