Opportunities and Challenges in Nano-structure Mediated Drug Delivery: Where Do We Stand?

Background: An effective drug delivery system delivers the therapeutically active moieties at the right time, rate and in a reproducible manner to effectively target sites for human illnesses. A major limitation associated with most of the currently available conventional and controlled release drug delivery devices is that not all the drug candidates are well absorbed uniformly locally or systemically. Methods: We searched for recent technological advancements in the development of nano-structure mediated drug delivery systems and their potential applications for the treatment of diseases. We focused on the challenges and bottlenecks to commercialization of nanomedicines. Results: Currently available conventional therapeutic devices require frequent drug administration due to the non-specific bio-distribution and rapid premature metabolism of free drug molecules. With the remarkable development of nanostructure devices during the last 2-3 decades, new drug delivery approaches based on nanotechnology have been receiving significant attention and gaining popularity. Researchers, both from the academia and industries are giving significant importance in the development of various nanostructure mediated drug delivery devices, as evident from numerous academic publications every year. Unfortunately, till date, few nanostructure mediated dosage forms have been commercialized and reached to the market. Current challenges associated with the manufacturing of such nanostructure based delivery systems are associated with their various physicochemical characteristics such as to balance the small particle size along with high drug loading, toxicity issues, and to obtain a stable nano drug delivery device. Conclusion: This review will help the formulation scientists to understand the critical strategies that are commonly used in the development of various nanostructure mediated drug delivery systems with a special emphasis on challenges which needs to be monitored and optimized during the product development to achieve a therapeutically active drug delivery system.