Nanocrystal Approaches for Poorly Soluble Drugs and their Role in Development of Marketed Formulation

Background: Poor solubility of the drug compounds is a significant problem in the pharmaceutical field; therefore, reducing particle size may be one of the most straightforward and efficient processes for enhancing the solubility of such compounds. Nanocrystal, a new carrier-free colloidal drug delivery system with a particle size ranging from 100 to 1000 nm, is thought as a viable drug delivery strategy to develop poorly soluble drugs. Objectives: This review focuses on the nanocrystal approaches and their uses in pharmaceutical applications. Also, various preparation methods of the nanocrystal are briefly described in this review. The paper also describes several factors involved in producing stable drug nanocrystals and provides suggestions for overcoming instability-related issues, like aggregation and Ostwald ripening. Finally, the specific opportunities and challenges that apply to nanocrystal technology are summarized in this paper. Methods: In this paper, we summarize and discuss the unique features of drug nanocrystals, including enhancement of dissolution velocity, adhesiveness to the surface, and saturation solubility. Nowadays, pharmaceutical industries are using different approaches to prepare the nanocrystal, like the bottom-up approach (precipitation), the top-down approach (wet milling, high-pressure homogenization), and some other combinational approaches. Results: Drug nanocrystals can be administered through different routes. Besides this, the various fabrication methods and characterization methods may be used to develop and scale up the production of drug nanocrystals. Conclusion: In this review article, the relevance of drug nanocrystals are presented and illustrated according to the research done by different researchers and finally concluded that marketed formulation related to nanocrystal are gradually in progression. However, some related and developed formulations are under clinical trial.