Abstract
This review describes the interaction between drug and pharmaceutical additives. The potential compatibility of several commonly used pharmaceutical additives with picotamide was evaluated using DSC. Mechanical treatments (blending, grinding, or kneading) of samples were also evaluated. Mechanical stress displayed an increased hygroscopicity of mixtures with glucose and lactose, as well as some solid-solid interactions with lactose. DSC studies have been carried out with amorphous solid dispersions of indomethacin and PVP. Values of glass transition temperature as a function of mixture composition followed the ideal Cordon-Taylor equation up to about 50% PVP. Thermal properties of ethenzamide in the mixtures with porous additives, porous crystalline cellulose and controlled pore glasses, were investigated by DSC. In the DSC curves of the mixtures of drug and the porous additives, an anomalous endothermic peak was observed. This endothermic peak was related to the adsorption of the drug into the pore of porous additives. Thermal behaviors of the mixture of benzoic acid or methyl-p-hydroxybenzoate with cyclodextrins were studied by DSC. Several thermal events were observed on the DSC curves, which were assigned to the inclusion formation and the release of the guest molecules from inclusion compound by X-ray diffractomertry and infrared spectrometry.
