Wet granulation drying

Development of solid dosage forms, more specifically tablets, involves three alternate processing methodologies—wet granulation, dry granulation, and direct compression (DC) (1). All these processes share the following common problems ... 

Polymorphic transformation can take place during pharmaceutical processing, such as particle size reduction, wet granulation, drying, and even during the compaction process.f Tests employed to determine crystal... 

Table 1 Typical unit operations involved in wet granulation, dry granulation, and direct compression...

Shear Extruder and hand screen Coarse Deagglomeration, wet granulation Dry material, hard, abrasive materials... 

For successful tableting, a material must have suitable flow properties to allow it to be fed to the tableting machine. Wet or dry granulation is used to improve the flow properties of materials. In the case of wet granulation, agitative granulation techniques such as fluidized beds or mixer granulators as discussed above are often employed. 

In wet granulation experiments, dried Ti02 particles were fed into the cylindrical air distributor (vessel), then the air distributor rotated and fluidization air was supplied. After a predetermined amount of binder liquid was sprayed, drying of products was conducted. 

Recently, two novel procedures have been described for the isolation of PHA granules based on air classification [81] or centrifugal fractionation [82] (Fig. 8). These two processes are related to the well established wet and dry milling methods used in the corn industry for the fractionation of corn seeds into endosperm, germ, and hull and for the isolation of starch grains [83]. 

The phase composition of glycine crystal forms during the drying step of a wet granulation process has been studied, and a model developed for the phase conversion reactions [88], X-ray powder diffraction was used for qualitative analysis, and near-infrared spectroscopy for quantitative analysis. It was shown that when glycine was wet granulated with microcrystalline cellulose, the more rapidly the granulation... 

Within the pharmaceutical industry, granulation is a widely used process to prepare drug substance and excipient particles for compression. " There are wet and dry granulation procedures herein high shear wet grannlation, fluid bed granulation and roller compaction will be discussed. 

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