Coamorphous Solids
Drug coamorphous systems is a relatively new approach in which the positive effects of the drug combination (coformer effect) and high thermodynamic functions of the amorphous phase (which confer solubility and dissolution advantage) are synergized to result in an improved pharmaceutical product. A coamorphous system is a multi-component single phase amorphous solid system which lacks periodic arrangement in the lattice and is associated by weak and discrete intermolecular interactions between the components. They can have short range ordering such as hydrogen bonding of carboxylic acids, carboxamides, phenols/alcohols, similar to amorphous solids of single component systems. A coamorphous solid may be contrasted with a cocrystal, salt or eutectic primarily by its amorphous nature in that it exhibits a broad hump (‘amorphous halo’) when subjected to powder X-ray diffraction. The identity and integrity of the components of coamorphous systems can be established by spectroscopy. Together with the more well known counterparts such as salts, eutectics and cocrystals, coamorphous solids are a new entry to pharmaceutical solid form space
A novel curcumin–artemisinin coamorphous solid: physical properties and pharmacokinetic profile