Introduction to Tablet Hardness Testing

Together with friability testing, the testing of a tablets hardness (or more correctly breaking force) plays a vital role in both product development and subsequent quality control.

In this test method, the tablet is placed between two platens (jaws), one of which is attached to a load cell and the other to a motor which provides the mechanical drive. During testing, the motorised jaw drives forward pressing the tablet against the fixed jaw until such time as the tablet breaks whereupon the motorised jaw retracts and the load required to break the tablet is recorded.

High hardness values may indicate, for example, increased disintegration times and reduced dissolution values. On the other hand, if hardness is too low then friability and hence % defective may well be too high. By exploiting the correlation between hardness, disintegration, dissolution, friability, percentage defective and weight variation, the various parameters can be manipulated to produce a dosage form with optimum characteristics.

Significant advances have been made in the field of tablet hardness testing in recent years. Copley Scientific offers a range of semi and fully automatic electronic testers incorporating these advances and varying in sophistication from simple hand held units for use on the production floor to fully automatic units incorporating print-out and data input/output facilities.

For comprehensive product details, specifications and part numbers, please request a copy of our brochure “Quality Solutions for the Testing of Pharmaceuticals”.