Current Status and Challenges of Analytical Methods for Evaluation of Size and Surface Modification of Nanoparticle-Based Drug Formulations

The present review discusses the current status and difficulties of the analytical methods used to evaluate size and surface modifications of nanoparticle-based pharmaceutical products (NPs) such as liposomal drugs and new SARS-CoV-2 vaccines. We identified the challenges in the development of methods for (1) measurement of a wide range of solid-state NPs, (2) evaluation of the sizes of polydisperse NPs, and (3) measurement of non-spherical NPs. Although a few methods have been established to analyze surface modifications of NPs, the feasibility of their application to NPs is unknown. The present review also examined the trends in standardization required to validate the size and surface measurements of NPs. It was determined that there is a lack of available reference materials and it is difficult to select appropriate ones for modified NP surface characterization. Research and development are in progress on innovative surface-modified NP-based cancer and gene therapies targeting cells, tissues, and organs. Next-generation nanomedicine should compile studies on the practice and standardization of the measurement methods for NPs to design surface modifications and ensure the quality of NPs.

Automated summary

This review discusses the challenges and current status of analytical methods for evaluating the size and surface modifications of nanoparticle-based pharmaceutical products, such as liposomal drugs and new SARS-CoV-2 vaccines. The difficulties include measuring a wide range of solid-state nanoparticles, evaluating the sizes of polydisperse nanoparticles, and measuring non-spherical nanoparticles. Although some methods have been established for analyzing the surface modifications of nanoparticles, their applicability to nanoparticle-based products is unclear. The review also highlights the need for standardization in the size and surface measurements of nanoparticles, including the lack of available reference materials and the difficulty in selecting appropriate ones for modified nanoparticle surfaces. Future research and development in nanomedicine should focus on the practice and standardization of measurement methods to design surface modifications and ensure nanoparticle quality.