PINPOINT enables non-destructive nanoscopic quality control of individual lipid nanoparticles and their mRNA cargo

Lipid nanoparticles (LNPs) and their mRNA cargo are crucial components in the development of mRNA therapeutics. However, traditional ensemble measurements fail to capture the vital differences in particle morphology and mRNA cargo distribution. Researchers have now developed PINPOINT, a novel platform for single-particle nanoscopy that enables the non-destructive, multiparametric profiling of preformulated LNP samples.

Using super-resolution imaging with Nile Red, PINPOINT can determine the size and morphology of the LNPs. An optimized permeabilization strategy allows for the selective access to encapsulated mRNA without damaging the LNP structure. By employing single-particle fluorescence measurements such as RiboGreen and sequence-specific probes, the platform can quantify and validate the amount of mRNA loaded into the nanoparticles and confirm their identity.

Comparing bare and encapsulated mRNA through PINPOINT reveals important kinetic and structural features, uncovering the previously hidden heterogeneity that cannot be detected by bulk assays. This new technology provides a quantitative framework for assessing LNP composition and payload distribution at the single-particle level, offering valuable insights for enhancing batch consistency and guiding the rational design of future mRNA delivery systems.