Tableting characteristics

Selection of the most suitable chemical form of the active principle for a tablet, while not strictly within our terms of reference here, must be considered. For example, some chloramphenicol esters produce little clinical response [13], There is also a significant difference in the bioavailability of anhydrous and hydrated forms of ampicillin [14], Furthermore, different polymorphic forms, and even crystal habits, may have a pronounced influence on the bioavailability of some drugs due to the different dissolution rates they exhibit. Such changes can also give rise to manufacturing problems. Polymorphism is, of course, not restricted to active ingredients, as shown, for example, in an evaluation of the tableting characteristics of five forms or sorbitol [15]. 

It has also been reported that the tableting characteristics of instant sorbitol result from its unique particle morphology [28]. Disintegration of instant sorbitol model tablets was found to be slower than tablets prepared using lactose, but this parameter can be optimized by proper disintegrant selection. 

A number of other studies have also shown that altering the physical, physicochemical, and mechanical properties of the material [7,26,27,40] can improve various sorbitol characteristics. Improvements in tableting characteristics, compressibility, and texture have been obtained by modifying the morphology and solid properties of the sorbitol powders. 

Sanghvi, P. R, Collins, C. C., Shukla, A. J. (1993). Evaluation of Preflo modified starches as new direct compression excipients 1. Tabletting characteristics. Pharm. Res., 10, 1597-1603. 

The material obtained from the kneading process should be, after drying and blending, compressed to tablets. The compressing capabilities and the tablet characteristics (content uniformity, thickness, hardness, friability, weight variances, and disintegration time) should meet the finished product specification for the compressed tablets. 

During scale-up of a bilayered tablet, it is necessary to determine the range of tamping that can be tolerated for a product. Typically, the tamping force and overall compression force are varied and the tendency to laminate is observed. In addition, the other tablet characteristics are also determined, e.g., hardness, thickness, weight uniformity, disintegration, and dissolution. 

One should consider desirable tablet characteristics from the very first stages of formulation to the final stage of process scale-up. These might include ... 

A final list should be kept in mind from the first formulation attempts through the production stage, i.e., the list of important tablet characteristics from a performance point of view. These, of course, are the specifications one sets on the final product, and they include ... 

Another scale-up approach, which is simple to understand, is to scale-up the compaction force based on the roller width. In this approach, once the desired tablet characteristics (i.e., tablet dissolution, granule flow, minimal tablet weigh variation, tablet hardness, and minimal tablet friability) are obtained, the ribbon compaction force is noted during processing from the known roll width. As the product is scaled up, the applied force is scaled up based on the roller width. Table 5 provides several examples of scale-up factors that can be used as a guide. This technique has been found to be successful, but may have some limitations as the entire scale-up relationship may not be linear. 

DuRoss, J.W. Modification of the crystalline structure of sorbitol and its effects on tableting characteristics. Pharm. Technol. 1984, 8, 42-53. 

Roblot, L. Puisieux, F. Duchene, D. A study on lubrication by magnesium stearate. The influence of the proportion of lubricant and the mixing process on the tablet characteristics. Labo. Pharma. Probl. Tech. 1983, 31, 843-847. 

Upon proper die fill, one must consider whether the material will form a tablet. The tableting characteristics of powders depend on the viscoelastic properties of the material. The process of compaction has been defined as the compression and consolidation of a two-phase system due to an applied load. The quality of the compact depends on the compression and consolidation of the powder mass, decompression of the compact, ejection from the die, and subsequent scrape-off from the lower punch. A schematic representation of the compression process is shown in Fig. 1. Because these viscoelastic properties are time dependent, both the magnitude and the rate of application (and release) of the compression force affect tablet quality. 

Hwang R-C, Peck GR. A systematic evaluation of the compression and tablet characteristics of various types of lactose and dibasic calcium phosphate. Pharm Teehnol 2001 25(6) 54, 56, 58, 60, 62, 64, 66, 68. 

Osberger TF. Tableting characteristics of pure crystalline fructose. Phamt Technol 1979 3(6) 81-86. 

The qualification of tablet characteristics was evaluated in a study of two algorithms soft independent modeling of class analogies (SIMCA) and quantile-BEAST [95]. The study involved tablet hardness, moisture content, dissolution rate, and degradant concentration. 

Tablet. Characteristic P NMR parameters of the compounds with the general formula [R2E "-P(H)SitBu3]2. Values of trans isomers values of the cis isomers are given in parentheses.

Sebhatu et al. studied the tableting characteristics of spray-dried lactose [52], which typically contains 15% amorphous material. The spray-dried material is known to absorb moisture when exposed to high... 

Hwang, R.-C. Peck, G.R. A systematic evaluation of the compression and tablets characteristics of various types of microcrystallme cellulose. Pharm. Technol. 2001, 25 (3), 112-132. 

Rojas, J Yepes, M Ciro, Y. Viscosity, Agglomeration Behavior and Tableting Characteristics of Cassava Starch Modulated by Wet Granulation A Comparative Study. In F. P. Molinari (Eds), Cassava Production, Nutritional Properties and Health Effects (1st. ed., 2014, 139-159). New York, NY Nova Science Publishers. 

Former DE, Anderson NR, Banker GS. Granulation and tablet characteristics. In Lieberman HA, Lachman L, eds. Pharmaceutical Dosage Forms. Tablets. Vol. 2. New York Marcel Dekker, Inc., 1982 Chap. 5. 

Kornchankul W, Parikh NH, Sakr A. Correlation between wet granulation kinetic parameters and tablet characteristics. Drugs Made Germany 2001 44 78-87. 

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