Moisture and gelatin effects on the interparticle attractive forces and the compression behaviour of oxytetracycline formulations.

The tensile strengths of compacts and/or tablets of the individual components and of granules prepared from an oxytetracycline formulation have been measured using the diametral compression test. Employing the theory of tensile strength, proposed by Cheng, it has been shown that increases in both moisture and gelatin contents of compacts and tablets increase the range of the attractive forces that operate between the granules. By studying the effects of moisture and gelatin on the compressional behaviour of the granules, it has been possible to classify them into different types. Fragmentation of granules occurs at packing fractions between 0-745 and 0-835, depending on their gelatin content.