Tablet formulations diluents

Formulation. Compressed tablet formulations contain several types of inert, adjuvant ingredients necessary for proper preparation and therapeutic performance. Tablets designed to be swallowed need diluent, disintegrating, binding (adhesive), and lubricating inert ingredients, whereas... 

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... 

Dissolution testing was performed on the five aberrant tablet formulations (n = 6 per formulation) and the target tablet formulation (n = 6) using the small volume dissolution method previously described. As shown in Table 10.6 and Fig. 10.6, the dissolution profiles for the aberrant tablet formulations with additional lubricant, diluent substitution, additional binder, and high tablet hardness differ from the profile... 

Microcrystalline cellulose (Avicel) is purified partially depolymerized cellulose, prepared by treating a-cellulose with mineral acids. In addition to being used as a filler, it is also used as dry binder and disintegrant in tablet formulations. Depending on the preparation conditions, it can be produced with a variety of technical specifications depending on particle size and crystallinity. It is often used as an excipient in direct compression formulations but can also be incorporated as a diluent for tablets prepared by wet granulation, as a filler for capsules and for the production of spheres. 

Compressed tablet formulations contain different types of ingredients necessary for proper preparation and therapeutic performance. The ingredients needed include diluents, disintegrating or binding (adhesive) additives, and lubricants. Tablets are designed to be dissolved slowly in the mouth and should not disintegrate quickly. Lactose... 

Cadila Laboratories Ltd. of Ahmedabad, India have developed an expert system for the formulation of tablets for active ingredients based on their physical, chemical, and biological properties. The system first identifies the desirable properties in the excipients for optimum compatibility with the active ingredient and then selects those that have the required properties based on the assumption that all tablet formulations comprise at least one binder, one disintegrant, and one lubricant. Other excipients such as diluents (fillers) or glidants are then added as required. 

The key component here is the diluent. This must not only possess those properties which are necessary for satisfactory tablet formulation, but also retain those properties when mixed with the other constituents of the formulation such as the active ingredient. 

Regulatory considerations also play a part in a decision whether or not to use the direct compression process. Several years may elapse between the finalizing of a tablet formulation and its marketing. During this period, stability testing of the product will have occurred. The formulator must be confident that a chosen direct compression diluent will still be available for a considerable time after product marketing otherwise reformulation with all its attendant delay and expense will be required. A number of direct compression diluents have been marketed that were withdrawn after only a few years because of lack of market penetration. 

Tribasic calcium phosphate is widely used as a capsule diluent and tablet filler/binder in either direct-compression or wet-granulation processes. The primary bonding mechanism in compaction is plastic deformation. As with dibasic calcium phosphate, a lubricant and a disintegrant should usually be incorporated in capsule or tablet formulations that include tribasic calcium phosphate. In some cases tribasic calcium phosphate has been used as a disintegrant. It is most widely used in vitamin and mineral preparations as a filler and as a binder. It is a source of both calcium and phosphorus, the two main osteogenic minerals for bone health. The bioavailability of the calcium is well known to be improved by the presence of cholecalciferol. Recent research reports that combinations of tribasic calcium phosphate and vitamin D3 are a cost-effective advance in bone fracture prevention. ... 

The main use of carboxymethylcellulose calcium is in tablet formulations see Table 1), where it is used as a binder, diluent, and disintegrant. Although carboxymethylcellulose calcium is insoluble in water, it is an effective tablet disintegrant as it swells to several times its original bulk on contact with water. Concentrations up to 15% w/w may be used in tablet formulations above this concentration, tablet hardness is reduced. 

Lactose is widely used in pharmaceutical formulations as a diluent and filler-binder in oral capsule and tablet formulations. It may also be used in intravenous injections. Adverse reactions to lactose are largely due to lactose intolerance, which occurs in individuals with a deficiency of the intestinal enzyme lactase, and is associated with oral ingestion of amounts well over those in solid dosage forms. 

Lactose is widely used in pharmaceutical formulations as a diluent in oral capsule and tablet formulations. It may also be used in intravenous injections. 

Maltodextrin is used in tablet formulations as a binder and diluent in both direct-compression and wet-granulation or... 

Mannitol is widely used in pharmaceutical formulations and food products. In pharmaceutical preparations it is primarily used as a diluent (10-90% w/w) in tablet formulations, where it is of particular value since it is not hygroscopic and may thus be used with moisture-sensitive active ingredients. 

Sodium alginate is used in a variety of oral and topical pharmaceutical formulations. In tablet formulations, sodium alginate may be used as both a binder and disintegrant it has been used as a diluent in capsule formulations. Sodium alginate has also been used in the preparation of sustained-release oral formulations since it can delay the dissolution of a drug from tablets, capsules, and aqueous suspensions. ... 

Sodium chloride has been used as a lubricant and diluent in capsules and direct-compression tablet formulations in the past, although this practice is no longer common. Sodium chloride has also been used as a channeling agent and as an osmotic agent in the cores of controlled-release tablets. It has been used as a porosity modifier in tablet coatings,and to control drug release from microcapsules. 

Sorbitol is used as a diluent in tablet formulations prepared by either wet granulation or direct compression. It is particularly useful in chewable tablets owing to its pleasant, sweet taste and cooling sensation. In capsule formulations it is used as a plasticizer for gelatin. Sorbitol has been used as a plasticizer in film formulations. ... 

Pregelatinized starch is a modified starch used in oral capsule and tablet formulations as a binder, diluent, and dis-integrant. ... 

Talc was once widely used in oral solid dosage formulations as a lubricant and diluent, see Table 1, although today it is less commonly used. However, it is widely used as a dissolution retardant in the development of controlled-release products. Talc is also used as a lubricant in tablet formulations in a novel powder coating for extended-release pellets and as an adsorbant. ... 

Tragacanth gum is also used similarly in cosmetics and food products, and has been used as a diluent in tablet formulations. 

Granulates of xylitol are used as diluents in tablet formulations, where they can provide chewable tablets with a desirable sweet taste and cooling sensation, without the chalky texture experienced with some other tablet diluents. Xylitol solutions are employed in tablet-coating applications at concentrations in excess of 65% w/w. Xylitol coatings are stable and provide a sweet-tasting and durable hard coating. 

The use of axial designs is illustrated in an experiment by Chariot, Lewis and Mathieu (13), who used it to investigate a conventional tablet formulation, containing a mixture of up to 5 diluents, disintegrant, binder, lubricant, binder (see table 9.10). The resulting axial design is shown in table 9.11. 

---