Factors affecting the preparation of nanocrystals: characterization, surface modifications and toxicity aspects

ABSTRACT

Introduction

The fabrication of well-defined nanocrystals in size and form is the focus of much investigation. In this work, we have critically reviewed several recent instances from the literature that shows how the production procedure affects the physicochemical properties of the nanocrystals.

Areas covered

Scopus, MedLine, PubMed, Web of Science, and Google Scholar were searched for peer-review articles published in the past few years using different key words. Authors chose relevant publications from their files for this review. This review focuses on the range of techniques available for producing nanocrystals. We draw attention to several recent instances demonstrating the impact of various process and formulation variables that affect the nanocrystals’ physicochemical properties. Moreover, various developments in the characterization techniques explored for nanocrystals concerning their size, morphology, etc. have been discussed. Last but not least, recent applications, the effect of surface modifications, and the toxicological traits of nanocrystals have also been reviewed.

Expert opinion

The selection of an appropriate production method for the formation of nanocrystals, together with a deep understanding of the relationship between the drug’s physicochemical properties, unique features of the various formulation alternatives, and anticipated in-vivo performance, would significantly reduce the risk of failure during human clinical trials that are inadequate.

KEYWORDS:

• Nanocrystals
• top-down methods
• bottom-up methods
• stabilizer
• surface modification
• toxicity

Article highlights

• Nanocrystals possess various advantageous properties, such as an increase in dissolution velocity, saturation solubility, supersaturation state, and decrease in fasted/fed state variability.

• Top-down, bottom-up, and combination processes are the main methods for the production of nanocrystals.

• Influence of process and formulation variables on the physicochemical properties of nanocrystals.

• Characterization methods to assess the size and morphology of nanocrystals were discussed.

• The effect of the presence of surface modifiers on the nanocrystals was discussed.

• Toxicological aspects and the application of nanocrystals through various delivery routes were also mentioned.

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.

Reviewer disclosures

Peer reviewers on this manuscript have no relevant financial or other relationships to disclose.

Additional information

Funding

This paper was not funded.