Abstract Differential Scanning Calorimetry was used as a screening technique for assessing the compatibility of Moxifloxacin hydrochloride with some currently employed pharmaceutical diluents. The data was supported by isothermal stability studies (IST) carried out at ambient conditions and at 50°C for the period of six months. Stability of drug in solution state in presence of diluents and the influence of pH were also investigated. DSC results revealed incompatibility of drug with neosorb, dextrose anhydrous and pearlitol on the basis of enthalpy loss and absence of melting endotherm of drug. Compatibility was predicted with microcrystalline cellulose, emcompress, dicalcium phosphate anhydrous, lycatab, lactochem fine powder and lactopress spray dried on the basis of DSC thermograms. In present work the ranking of diluents in decreasing order of stability obtained from IST and the results obtained from DSC were compared and correlated..
Keywords: Moxifloxacin hydrochloride, DSC, isothermal stability studies, compatibility, enthalpy, diluents