Enumeration of colloidal sub-micron particles using tunable resistive pulse sensing

Tunable resistive pulse sensing (TRPS) has been implemented alongside dynamic light scattering (DLS) and scanning electron microscopy (SEM) to characterise a particle size distribution between 400 nm and 1 μm effective diameter. The carboxylate polystyrene particles studied were synthesised by dispersion polymerisation, and overall the data suggest that there are two modal peaks in the distribution. TRPS data indicated that the primary mode was near 630 nm, with a lesser peak near 830 nm. Two pores of different sizes were used for TRPS, and the lower size measurement threshold was apparent for both pores. High throughput particle-by-particle size measurement techniques such as TRPS are of interest for measuring synthetic particles, with potential roles including quality control and compliance, in addition to fundamental studies.