A Brief Discussion of Multi-Component Organic Solids: Key Emphasis on Co-Crystallization

Co-crystallization (CCs) is a less studied phenomenon related to its applicability and reliability as it is directly related to the generation of newer multicomponent solids like co-crystals (CS), eutectic, salts or solid solutions etc. having improved physicochemical properties compared to their pure components. Further, the design and structural aspects of these multicomponent systems remain hindered compared to other techniques such as nanotechnology or solid dispersion. CC is a newer technique to modify the physicochemical as well as pharmaceutical characteristics of various drugs having issues like solubility, stability, etc. without altering or hindering their pharmacological activities. For drug delivery purpose, CC process has numerous advantages over nanotechnology and solid dispersion drug delivery techniques. CCs can modify the physicochemical properties of active pharmaceutical ingredients (API) have issues like sensitivity toward environmental hazards like temperature, moisture, or photostability issues. The availability of large numbers of conformers makes this technique favorable for the researchers in designing CS of newer and older. Although, solid dispersion and nanotechnology techniques are being utilized to a larger extent still there are some drawbacks of these techniques like stability, toxicological factors and protection from environmental factors need to be considered, while the CCs process drastically modifies the various pharmaceutical parameters without altering the pharmacological properties of API's. Salts, design of CS, their methods of preparation, and their application in various fields with special emphasis on their applicability in the pharmaceutical industry.