Physico-chemical characterisation of three-component co-amorphous systems generated by a melt-quench method

The purpose of this work was to evaluate the possibility of creating a ternary co-amorphous system and to determine how the properties of a co-amorphous material are altered by the addition of a selected third component. Piroxicam and indomethacin form a stable co-amorphous with the T-g above room temperature. The third component added was selected based on tendency to crystallise (benzamide, caffeine) or form amorphous (acetaminophen, clotrimazole) on cooling. Generated co-amorphous systems were characterised with TGA, HSM, DSC, FTIR and XRD. Stable ternary co-amorphous systems were successfully generated, which were confirmed using XRD, DSC and FTIR analysis. In all cases, T-g of the ternary system was lower than the T-g of the binary system, although higher than that of the individual third component. Upon storage for 4 weeks, all created ternary systems showed significantly smaller variation in T-g compared to the binary system. Stable three-component co-amorphous systems can be generated via melt-quench method using either a crystalline or an amorphous third component. Addition of third component can alter the T-g of co-amorphous system and in all cases created more stable co-amorphous system upon storage. Physical parameters may not be sufficient in predicting the resulting T-g; therefore, knowledge of chemical interaction must be brought into equation as well.