Send to

Choose Destination
See comment in PubMed Commons below
J Pharm Sci. 2012 Dec;101(12):4501-15. doi: 10.1002/jps.23313. Epub 2012 Sep 17.

An exact model for predicting tablet and blend content uniformity based on the theory of fluctuations in mixtures.

Author information

Cima Labs Inc., R&D Formulations, 7325 Aspen Lane, Brooklyn Park, Minnesota 55428, USA.


Content uniformity (CU) of tablets is a critical property that needs to be well controlled in pharmaceutical products. Methods that predict the CU accurately can greatly help in reducing the development efforts. This article presents a statistical mechanical framework for predicting CU based on first principles at the molecular level. The tablet is modeled as an open system that can be treated as a grand canonical ensemble to calculate fluctuations in the number of granules and thus the CU. Exact analytical solutions to hard sphere mixture systems are applied to derive an expression for the CU and elucidate the different factors that impact CU. The model was tested against literature data and a large set of tablet formulations specifically made and analyzed for CU using a model active pharmaceutical ingredient. The formulations covered the effect of granule size, percentage loading, and tablet weight on the CU. The model is able to predict the mean experimental coefficient of variation (CV) with good success and captures all the elements that impact the CU. The predictions of the model serve as a theoretical lower limit for the mean CV (for infinite batches or tablets) that can be expected during manufacturing assuming the best processing conditions.

[Indexed for MEDLINE]
PubMed Commons home

PubMed Commons

How to join PubMed Commons

    Supplemental Content

    Full text links

    Icon for Elsevier Science
    Loading ...
    Support Center