EFFECT OF A PARTICLE ENGINEERING PROCESS ON POLYMORPHIC TRANSITION OF PYRAZINAMIDE

Objective: The objective of this work was to investigate the effect of processing on physicochemical properties of spray dried Pyrazinamide. Methods: Pyrazinamide was spray dried using several spray drying conditions, FTIR, XRD and thermal analysis were undertaken for all samples. A comparison of crystalline/amorphous nature of the starting material as well as processed materials was carried out. Results: The unprocessed material was a typical crystalline material composed of a mixture of alpha and gamma polymorphic forms of pyrazinamide. In contrast spray dried materials showed other mixtures of different polymorphs of  pyrazinamide based on spray drying conditions. In other words, the solid state of spray dried material was dependent on processing parameters (solvent systems, inlet temperature), which may indicate the effect of processing conditions on the solid state of Pyrazinamide. Conclusion: Processing of Pyrazinamide without excipients gave different polymorphs, according to the solvent mixture used in the spray drying process