Formulation Optimization For Tabletting Applications

As seen in the Fall 2007 Pharmaceutical Online Solutions Update

Tablet production is an essential operation for the pharmaceutical industry, considering the majority of drugs are being delivered in this form. Tablet presses operating on the principle of direct compression have been developed over several decades and it is now possible to make in excess of one million tablets per hour. Developing formulations that process well in these units to consistently deliver uniform tablets with the required properties, remains an ongoing challenge.

The Challenges Posed By Tabletting
With direct compression, tablet ingredients are fed to a press as a blended powder. The blend contains various components — filler, inert carrier, active pharmaceutical ingredient (API), and lubricant — each of which fulfils a different function in terms of tablet or processing performance. Wet or dry granulation processes may be used to improve the flowability of the blend.

Tablet quality is quantified in terms of strength, weight, dimensions, and API content, the required properties being produced through control of the flowability and compressibility of the mix. This is achieved by manipulating variables such as particle size and shape, surface texture, and water content, and by addressing fundamental issues such as excipient choice and the concentration of each component in the final formulation. Quality may be highly dependent on processing speed so productivity may be adversely affected if flow properties are not optimal.