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Microstructure of Tablet—Pharmaceutical Significance, Assessment, and Engineering

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Abstract

Purpose

To summarize the microstructure – property relationship of pharmaceutical tablets and approaches to improve tablet properties through tablet microstructure engineering.

Method

The main topics reviewed here include: 1) influence of material properties and manufacturing process parameters on the evolution of tablet microstructure; 2) impact of tablet structure on tablet properties; 3) assessment of tablet microstructure; 4) development and engineering of tablet microstructure.

Results

Microstructure plays a decisive role on important pharmaceutical properties of a tablet, such as disintegration, drug release, and mechanical strength. Useful information on mechanical properties of a powder can be obtained from analyzing tablet porosity—pressure data. When helium pycnometry fails to accurately measure true density of a water-containing powder, non-linear regression of tablet density—pressure data is a useful alternative method. A component that is more uniformly distributed in a tablet generally exerts more influence on the overall tablet properties.

Conclusion

During formulation development, it is highly recommended to examine the relationship between any property of interest and tablet porosity when possible. Tablet microstructure can be engineered by judicious selection of formulation composition, including the use of the optimum solid form of the drug and appropriate type and amount of excipients, and controlling manufacturing process.

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ACKNOWLEDGMENTS AND DISCLOSURES

I thank Shubhajit Paul, Chenguang Wang, and Jiangnan Dun for useful comments during the preparation of this manuscript. Data used in Fig. 2 were collected by Shubhajit Paul.

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  1. Pharmaceutical Materials Science and Engineering Laboratory, Department of Pharmaceutics, College of Pharmacy, University of Minnesota, 9-127B Weaver-Densford Hall, 308 Harvard Street S.E., Minneapolis, Minnesota, 55455, USA

    Changquan Calvin Sun

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Sun, C.C. Microstructure of Tablet—Pharmaceutical Significance, Assessment, and Engineering. Pharm Res 34, 918–928 (2017). https://doi.org/10.1007/s11095-016-1989-y

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