• NATALIA C. D. O. NASCIMENTO Industrial Pharmacy Residency Program, Center of Medical and Pharmaceutical Sciences, State University of Western Parana, Cascavel, Parana, Brazil
  • EMERSON M. BOLDO Industrial Pharmacy Residency Program, Center of Medical and Pharmaceutical Sciences, State University of Western Parana, Cascavel, Parana, Brazil




Hardness, Post-compression, Povidone, Fluidized bed, V blender


Objective: This work evaluated the post-compression hardness gain of Metformin tablets made from two granulates of the same formulation, but with different formation principles, one by the fluidized bed and the other in a V-shaped mixer.

Methods: The base granulate for the production of the tablets was prepared using Metformin HCL as the main active ingredient. After compression, the prepared tablets were tested with different evaluation parameters like relative humidity, apparent and compacted density, granulometric dispersion, hardness, moisture content, and friability for complete characterization.

Results: All prepared samples were within the pre-established humidity ranges (MT1 = 3.31%, MT2 = 2.72%, MT3 = 1.73%, LF1 = 3.25%, LF2 = 2.43% and LF3 = 1.79%). The density determination showed that the granules produced in the fluidized bed are less dense than those of the V mixer. LF2 sample had an apparent density of 0.525 g/ml and a compacted density of 0.546 g/ml, while the MT2 sample had an apparent density of 0.711 g/ml and a compacted density of 0.738 g/ml, corroborating the greater porosity of granules produced in a fluidized bed. It was found that there is a difference in the increase in hardness between the two granulation methods. The tablets manufactured from the granules elaborated in a V-shaped mixer showed a greater gain in comparison with those produced in the fluid bed. The MT1 sample had the highest gain percentage, reaching 99.47%, 48 h after compression. The MT2 sample obtained, for the same time, 76.34%, at a much slower speed than MT1. As for the other samples, all increased between 24 and 42%. These results are justified by the migration of agglutination liquid that occurs during the drying step.

Conclusion: This work demonstrated that the product Metformin 500 mg tablet has increased hardness after compression, with most significance in the first hour after the procedure. It was possible to verify that the tablets made from the granules produced in a V-shaped mixer have a greater increase in hardness than those produced by the fluidized bed, in the same humidity range.


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How to Cite

NASCIMENTO, N. C. D. O., and E. M. BOLDO. “EVALUATION OF MECHANICAL STRENGTH AFTER COMPRESSION OF METFORMIN 500MG TABLETS PRODUCED BY DIFFERENT WET ROUTES”. International Journal of Pharmacy and Pharmaceutical Sciences, vol. 13, no. 3, Feb. 2021, pp. 30-34, doi:10.22159/ijpps.2021v13i3.40311.



Original Article(s)