Nanocrystal: a novel approach to overcome skin barriers for improved topical drug delivery

ABSTRACT

Introduction: Skin is an important route of drug delivery for the treatment of various dermatological conditions. The advent of nanotechnology is paving the roadmaps for topical drug delivery by providing sustained release as well as maintaining a localized effect, outweighing the toxicity concern.

Area covered: This review highlighted the morphology of skin, its barrier nature as well as drug penetration pathways after topical application of formulations. The existing methods to improve topical drug delivery, by infringing or permeating the skin barriers, are discussed. This context concretes the foundation to accentuate the need for the development of nanocrystal-based topical formulation. The mechanism of drug release, immediate as well as sustained release, after topical administration of drug nanocrystals is also elaborated. The special emphasis is given on the breakthrough achieved, in topical drug delivery using drug nanocrystals, so far in the plethora of literature, patents, and products, under clinical trial as well as in the market.

Expert opinion: The current research on nanocrystals for topical drug delivery is highlighting the breakthroughs achieved so far. The output of these research envisages that topical nanocrystals based formulations can be a novel strategy for the drugs which are facing solubility, bioavailability and toxicity concerns.

KEYWORDS:

• Skin
• skin barriers
• topical drug delivery
• nanotechnology
• nanocrystals

Article Highlights

• The barriers for topical drug delivery are discussed

• Role of nanotechnology to overcome barriers in topical drug delivery

• Advantages of nanocrystal over other nanotechnology-based formulations in topical drug delivery are highlighted

• Methods of preparation for drug nanocrystals are described

• Current research findings, patents, and marketed products based on nanocrystals for topical application are summarized with their future prospects

This box summarizes key points contained in the article.

Acknowledgments

Authors are thankful to Prof. Anuradha Gajjar for kindly revising the English version of the manuscript.

Declaration of interest

The authors have no relevant affiliations or financial involvement with any organization or entity with a financial interest in or financial conflict with the subject matter or materials discussed in the manuscript. This includes employment, consultancies, honoraria, stock ownership or options, expert testimony, grants or patents received or pending, or royalties. Peer reviewers on this manuscript have no relevant financial or other relationships to disclose.

Additional information

Funding

 This work was supported by Department of Science and Technology, Ministry of Science and Technology, Government of India (DST-INSPIRE) under grant INSPIRE FELLOWSHIP (IF140936) to Viral Patel.