Abstract

Background: Most of the chemical substances which emerge out as potential drug candidates (Active Pharmaceutical Ingredients) are either weak acids or weak bases. The poor aqueous solubility of these drug substances is a common concern. Several R&D centers are focused on developing suitable, economic, simpler and more feasible solubility enhancement techniques for increasing the solubility and thereby bioavailability of such drug substances. Nanocrystals are one of the preferred approaches for solubility enhancement in the last few decades.

Methods: Nanocrystal as a solubility enhancement approach is widely explored and discussed by many researchers. Despite being the most simple and feasible technique, nanocrystal formulation has its own limitations. The present review enlightens some novel technologies which can overcome disadvantages of conventionally well-established bottom-up and top-down techniques used for nanocrystal formulation.

Results/Applications: The present review summarizes and also highlights the correlation between some novel findings like reduction in the melting point of drug and nanocrystal formulation. The review also includes a special section emphasizing on the patents granted in the field of nanocrystals. The review includes more than ten patents focusing on several aspects of nanocrystal formulations as manufacturing methods, formulation components and conventional and novel applications of nanocrystals in new and hybrid forms. Aspects related to advantages of nanocrystals over other formulation approaches, targeting (Active and Passive) through nanocrystal formulations and issues related to nanotoxicity are also reviewed and discussed in the present article.

Conclusion: The findings, research outcomes and patents related to nanocrystal formulations, reported in the present review confirm the potential of the stated system as a drug delivery tool. The review emphasizes on the urge for further exploration required in the area of nanocrystal system for enhancing its efficiency as a drug delivery and a diagnostic tool.

Keywords: Bioavailability enhancement, drug targeting, nanocrystals, nanotoxicity, quantum dots, solubility enhancement.

Graphical Abstract