Simultaneous, Single-Particle Measurements of Size and Loading Give Insights into the Structure of Drug-Delivery Nanoparticles
Journal article, 2021
Nanoparticles are a promising solution for delivery of a wide range of medicines and vaccines. Optimizing their design depends on being able to resolve, understand, and predict biophysical and therapeutic properties, as a function of design parameters. While existing tools have made great progress, gaps in understanding remain because of the inability to make detailed measurements of multiple correlated properties. Typically, an average measurement is made across a heterogeneous population, obscuring potentially important information. In this work, we develop and apply a method for characterizing nanoparticles with single-particle resolution. We use convex lens-induced confinement (CLiC) microscopy to isolate and quantify the diffusive trajectories and fluorescent intensities of individual nanoparticles trapped in microwells for long times. First, we benchmark detailed measurements of fluorescent polystyrene nanoparticles against prior data to validate our approach. Second, we apply our method to investigate the size and loading properties of lipid nanoparticle (LNP) vehicles containing silencing RNA (siRNA), as a function of lipid formulation, solution pH, and drug-loading. By taking a comprehensive look at the correlation between the intensity and size measurements, we gain insights into LNP structure and how the siRNA is distributed in the LNP. Beyond introducing an analytic for size and loading, this work allows for future studies of dynamics with single-particle resolution, such as LNP fusion and drug-release kinetics. The prime contribution of this work is to better understand the connections between microscopic and macroscopic properties of drug-delivery vehicles, enabling and accelerating their discovery and development.
genetic medicines
microscopy
vaccines
drug-delivery
nanomedicines
lipid nanoparticles
single-molecule
Author
Albert Kamanzi
McGill University
University of British Columbia (UBC)
Michael Smith Laboratories
Yifei Gu
McGill University
Radin Tahvildari
McGill University
Zachary Friedenberger
McGill University
Xingqi Zhu
McGill University
Romain Berti
McGill University
Michael Smith Laboratories
Université de Montréal
Marty Kurylowicz
Université de Montréal
McGill University
Dominik Witzigmann
University of British Columbia (UBC)
Jayesh A. Kulkarni
University of British Columbia (UBC)
Jerry Leung
University of British Columbia (UBC)
John Andersson
Chalmers, Chemistry and Chemical Engineering, Applied Chemistry
Andreas Dahlin
Chalmers, Chemistry and Chemical Engineering, Applied Chemistry
Fredrik Höök
Chalmers, Physics, Nano and Biophysics
Mark Sutton
McGill University
Pieter R. Cullis
University of British Columbia (UBC)
Sabrina Leslie
Michael Smith Laboratories
McGill University
University of British Columbia (UBC)
ACS Nano
1936-0851 (ISSN) 1936-086X (eISSN)
Vol. 15 12 19244-19255Subject Categories
Pharmaceutical Sciences
Other Chemistry Topics
DOI
10.1021/acsnano.1c04862
PubMed
34843205