Wet granulation process

Enzymes. Where tablets are not naturally very cohesive and have thus been manufactured by a wet granulation process involving one of the binders listed in Table 8, addition of small quantities of appropriate enzyme may be sufficient to produce rapid disintegration. It has also been proposed that disintegration action might result from expansion of the entrapped air due to generation of heat of wetting when the tablet is placed in a fluid. This concept has received little attention. 

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... 

In 2005, Rantanen et al. used on-line NIRS to monitor a laboratory-scale high shear wet granulation process. The study was a central-composite circumscribed design consisting of 17 runs and 3 variables ... 

Given that the introduction of solvent obviously produces wet granules, the wet granulation process includes a drying step. Drying typically occurs in a fluid bed dryer. But there are other options, such as microwave vacuum dryers. In 1994, White applied on-line NIRS to monitor moisture content and predict drying end point in two TK Fielder microwave dryers. The NIR spectral data were correlated to off-line Karl Fischer measurements which resulted in a standard error of prediction equal to 0.6% when the samples... 

S. Watano, Direct control of wet granulation processes by image processing system, Powder TechnoL, 117(1-2), 163-172 (2001). 

As the behavior of the wet granulation process cannot be described so far adequately by mathematical equations, the dimensionless groups have to... 

In the case of the wet granulation process in a mixer/kneader, the granulation process can be easily monitored by the determination of the power consumption (6-9) (Fig. 1). 

When compared with direct compression results, the dry granulation processes enhance the flow of the powder and decrease the variability of the AUC, the major response. Nevertheless, this variability and the variability of the drug dissolved at 8 h (T7) are greater than the fixed optimal values, particularly for the compaction processes. From the results it is seen that the wet granulation process gave a powder presenting an adequate or better result than the other processes ... 

Wet granulation can be used to improve the flow of the material to be processed. Additionally, it is used to improve the uniformity of the material. It may also be used to increase the density of the materials to allow for better processing downstream. Wet granulation processes require the handling of solutions. Typically, there is minimal dust generation. Additionally, processes involve the use of alcohol or water. Facilities should include drying capabilities either built into the granulators or as a separate functional area. Utilities required include electricity, compressed air, and steam. 

List of Quality Attributes and Potential Process Parameters for a Wet Granulation Process... 

Lipps, D. and Sakr, A.M. Characterization of wet granulation process parameters using response surface methodology. 1. Top-spray uidized bleffharm. Sci83 (1994), 937. 

S.M. Iveson, J.D. Litster, K. Hapgood, B.J. Ennis, Nucleation, growth and breakage phenomena in agitated wet granulation processes a review, Powder Technol. 117 (2001) 3-39. 

The steps utilized in a wet granulation process are summarized below and are outlined in Fig. 5.2. 

Figure 5.2 Scheme showing the steps in a wet granulation process. 

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