Tablet manufacture excipients

There are other components in the tablet, composing the remaining 16% of the tablet. These excipients were not included in the initial model, so the results for the three API components need to be normalized to then-expected contribution to the whole tablet. When normalized to a total contribution of 84%, the abundance estimations are 36% for acetaminophen, 37% for aspirin and 11% for caffeine. These valnes compare favorably with the manufacturers label claim of 37% for acetaminophen, 37% for aspirin, and 10 % for caffeine. 

Although DC seems to be the method of choice for tableting, wet granulation is still widely used in various product manufacturing. Excipients such as MCC lose compressibility upon addition of water, a phenomenon called quasi-hornification (49). This property is improved, however, when it is coprocessed into SMCC. 

Figure 5 Scans of commonly used excipients for tablet manufacture. Key-MCC (Avicel PH101),—MCC (Avicel Ph200), Lactose (Foremost 325),—dibasic calcium phosphate (di-tab) and—Mg Stearate.

Direct compression is a simpler alternative tablet manufacturing method. With direct compression, tablets are compressed directly from a powder mixture of an API and appropriate excipients. Like granulation methods, this approach is also based on the required flow, compressibility, and compactibility of a formulation. Direct compression offers both time and economic advantages by eliminating intermediate granulating and drying steps. 

Microcrystalline cellulose - mainly used as a binder or diluent in solid oral dose formulations. It also has lubricant and disintegrant properties which make it a useful excipient in tablet manufacture. 

Lactose is one of the most widely used excipients in tablet manufacture. It is available in a number of different forms, differing in hydration and crystal states. Isolation and purification may involve treatment with sulphur dioxide. However, there are no reports of complications from residues of this powerful oxidizing agent. 

The term direct compression was initially applied to the formation of compacts from materials that required no pretreatment and the addition of no additives or excipients. As such, it was only used for inorganic materials such as potassium bromide. Today, within the pharmaceutical industry, the term is used for tablet manufacture that does not involve the pretreatment of the drug substance apart from blending with excipients. 

Content uniformity is a measurement of the variation in the active ingredient from one unit to the next. As drug products are manufactured, excipients and fillers are added. Factors such as densities, particle sizes, and particle shapes may contribute to the differences in uniformity. Therefore, uniformity is necessary to assure the individual unit conforms to compendial acceptance criteria of content uniformity. More information on the requirements of this test can be found in USP/NF General Chapter < 905 >. These are similar to the requirements of the European and Japanese Pharmacopeia. Typically, 10 tablets are analyzed and the average and %RSD are reported. The procedure usually is an HPLC test however, UV and other methods. 

Bioavailability, Bioequivalence, and Pharmacokinetics. Bioavailabihty can be defined as the amount and rate of absorption of a dmg into the body from an adrninistered dmg product. It is affected by the excipient ingredients in the product, the manufacturing technologies employed, and physical and chemical properties of the dmg itself, eg, particle size and polymorphic form. Two dmg products of the same type, eg, compressed tablets, that contain the same amount of the same dmg are pharmaceutical equivalents, but may have different degrees of bioavailabihty. These are chemical equivalents but are not necessarily bioequivalents. For two pharmaceutically equivalent dmg products to be bioequivalent, they must achieve the same plasma concentration in the same amount of time, ie, have equivalent bioavadabihties. 

The influence of the actual manufacturing process can also affect the contribution of the diluent to the final characteristics of the product. For instance, Shah et al. [45] demonstrated that the release of drug from tablets formulated with soluble excipients may be more... 

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