Granules properties

Influence of sieve mesh sizes (if sieves are used) on the granulation properties (e.g., particle size distribution, moisture content, poured density, tap density, and flow capacity)... 

Binder Different binders have different binding properties and the concentration of an individual binder may have to be changed to obtain similar binding of primary particles. Thus, the type of binder, and binder content in the formulation and concentration of the binder have major influence on granule properties. These properties include friability, flow, bulk density, porosity, and size distribution. 

During process development, samples at various stage of granulation should be obtained and analyzed. To maintain similar bed expansion throughout the whole granulation process, the superficial gas velocity should be increased based on granule properties. The amount of fluidization gas required for the bed expansion can be estimated from Eqs. (4.6)-(4.8). The inlet airflow was found to have little impact on granule size.37... 

Table 4.4 summarizes the main important parameters for the fluidized bed granulation process and their impact. Granule properties can be affected by several parameters. Granule size, for example, can be affected by starting material properties, atomization, spray liquid properties, and attrition. It is very important to take a comprehensive review of all the process parameters for process development. 

W.B. Pietsch, Granulating pan operating variables and their effect on granulate properties, Aufbereit.-Tech., 7 (4) (1966) 177—191. 

MacMasters, M. M. 1964. Microscopic techniques for determining starch granule properties. In Methods in Carbohydrate Chemistry. (R. L. Whistler, ed.), Academic Press, New York. 

The bonding forces in a dry aggregate are important to granulation properties such as granule integrity, flow-ability, friability, density, compressibility, and size for down-stream manufacturing process steps. Rumpf and coworkers described the bonding mechanisms... 

End-point can be defined by the formulator as a target particle size mean or distribution. Alternatively, the end-point can be defined in rheologieal terms. It has been shown that once you have reaehed the desired end-point, the granule properties and the subsequent tablet properties are very similar regardless of the granulation proeessing factors, such as impeller or ehopper speed or binder addition rate. I would call this the prineiple of equifinality. ... 

Power consumption or torque fluctuations are influenced by granule properties (PSD, shape index, and apparent density) and the granulation time. Fluctuation of torque/power consumption and intensity of spectrum obtained by FFT analysis can be used for end-point determination. 

We have seen that there exists a sort of principle of equifinality that states An end-point is an end-point is and end-point, no matter how it was obtained. Different processing pathways can lead to different end-points, each with its own set of granulation properties. However, once an end-point is reached, it is characterized by certain numerical values of the dimensionless variables describing the process, and these values will be independent of scale. 

Alderborn, G. Granule properties of importance to tablet-ing. Acta Pharm. Seuc. 1988, 25, 229-238. 

Herman J, Remon JP. Aluminium-magnesium hydroxide tablets effect of processing and composition of granulating solution on the granule properties and in vitro antacid performance. Drug Dev Ind Pharm 1988 14 1221-1234. 

A specific example of granulation properties in the combination vacuum/micro-wave technology versus forced air drying is reviewed in Ref. 38. The article describes the influence of these drying methods on attributes such as specific surface area, porosity, friability, hardness and morphology. 

Material parameters Granulation conditions Drying conditions Granule properties Tablet properties... 

Vaerenbergh V. The influence of a swinging bowl on granulate properties. Pimm Tech Eur 2001 I3(3) 36-43. 

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