Pre-granulation and formulation of granules

Granulation is a commonly used technique for particle enlargement in pharmaceutical manufacturing – mixtures are agglomerated into semi-permanent aggregates by mixing active pharmaceutical ingredients, known as APIs and excipients. The latter has numerous functions, for instance, those that promote binding and improve tablet hardness, such as binders and disintegrants, or enhancing patient acceptance with flavors. Other excipients, such as hydrophilic polymers and wetting agents, optimize or modify drug release, while antioxidants enhance stability.

The granulation process can be divided into two main types: wet and dry granulation. Dry granulation is used when ingredients are moisture or heat-reactive. It is an efficient process due to simple equipment and minimum processing required. On the other hand, wet granulation is a complex process with various pharmaceutical granulation equipment and steps. Although more costly, it is also a more widely used process, especially useful in processing soluble low-dose drugs.

Pharmaceutical granulation equipment for wet, dry, and direct compression processes

As the names imply, the process of wet granulation utilizes a liquid, while dry granulation requires no liquid. The first step in the dry granulation process is weighing all the ingredients which are then mixed until they form a uniform powder. In a process called slugging, the mixture is compressed into pallets and broken into smaller pieces using a hammer mill. To achieve a uniform blend, excipients such as lubricants and disintegrants are added.

Innovating high-shear mixers in the granulation industry

Although high-shear mixers have stood the test of time, being used in granulation processes for over six decades, there have been some recent innovations in the pharmaceutical industry. Namely, high-shear mixers can work under a vacuum and dry the wet mass within itself or are provided with fluid bed processors so that all the stages are carried out within the same mainframe equipment. These mixers have the capability to handle very fine particle coating of 75 to 100 microns. The popularity of such mixers lies in their simplicity and the fact that they are used as one-stage one-step equipment from the start till the loading of the granules atop the compression table.