A material sparing test to predict punch sticking during formulation development

Abstract

Context: A qualitative and material sparing test for punch sticking was developed as a predictive development screening tool for comparison of formulation strategies and processing methods to eliminate punch adhesion.

Objective: To develop a predictive test for a formulation’s potential to adhere to tablet punches during compression.

Materials and methods: Two proprietary compounds, A and B, with histories of punch sticking during manufacturing but not in development, were formulated with microcrystalline cellulose, lactose, croscarmellose sodium, and magnesium stearate. Matching placebos were also prepared by the same methods. Flat faced bevel edge (FFBE) punches of 1/2″ diameter were compared with 1/4″ SRC punches and 1/4″ Flat Faced (FF) punches for adhesion potential using a Kilian rotary tablet press and a Huxley Bertram compaction simulator.

Results and discussion: Formulation accumulated on the punches after compression, which indicated potential for punch sticking that resulted in defective tablets with successive compactions. In all cases, only active formulations adhered to the FFBE and FF punches during tableting runs and with fewer compactions than the SRC punches. Those APIs were then reformulated and successfully manufactured using the predictive test results. Reducing the punch size to 1/4″ permitted testing with 50 g of formulation, a ten-fold reduction in consumption compared to the 1/2″ punches.

Conclusion: Flat surfaced punches were shown to be more challenging to adhesive formulations than SRC punches. Adhesive formulations were reformulated and successfully manufactured without punch sticking.

Keywords::

• Punch adhesion
• sticking
• punch filming
• compression
• sticking test
• tablet

Acknowledgements

The authors thank Bruce Green for assistance with the Kilian Press, and Angela Hausberger for editorial assistance.

Declaration of interest

The authors report no conflicts of interest.