TRPS analysis enables viral particles to be counted directly, avoiding the need for the multiple steps or the destruction of virus particles. TRPS is a single-particle method which enables fast measurements, not requiring pre-analytical processing, fluorescent labelling, or highly skilled protocols, highlighting the shift in the field toward direct measurement techniques. Directly and accurately quantify viral particles without pre-analytical processing or highly skilled protocols, to optimise different stages of vaccine manufacture process. The small size of some viruses/VLPs is a challenge for other quantification techniques, however TRPS provides an accurate picture of the true particle size distribution and heterogeneity of a sample. Unlike some optical-based techniques which provide an average particle size, TRPS provides single-particle measurements and can precisely resolve multimodal or polydisperse samples. TRPS can be used to create both a better understanding of manufacturing processes and an accelerated purification optimisation when manufacturers are informed of accurate size distribution of virus particles. Distinguish between viruses/VLPs of different sizes with nanometre precision and discriminate between populations with different surface properties with potential diagnostic applications. The ability of TRPS technology to measure particle-by-particle offers a more comprehensive characterisation of virion/VLP preparations, by simultaneously quantifying key physical parameters with high accuracy and precision. TRPS determines virus/VLP concentration, size, and zeta potential by measuring the characteristics of a blockade created when particles pass through the nanopore. The ability of TRPS to analyse heterogenous populations with high resolving power enables discriminating subpopulations of viruses within a sample when species exhibit even slight differences in diameters or zeta potentials. Very small changes in zeta potential or particle size of viruses/VLPs in response to the binding of an antibody or aptamer can be evaluated using TRPS, allowing identification and specific quantification of subpopulations effectively labelled, leading to a reliable assessment at different stages of any assay optimisation process, especially important in diagnostics development.
