Nanopipet‐Based Resistive Pulse Sensing to Follow Alterations in the Size and Concentration of Nanoparticles During Membrane Filtration

Abstract

We propose a calibration‐free resistive pulse sensing (RPS) methodology based on nanopipets to follow the size and concentration changes of nanoparticles during size‐selective separation processes. The study was performed with monodisperse latex nanoparticles and their mixtures that were subjected to separation procedures such as filtration through track‐etch membranes of various pore diameters as well as centrifugal filtration. The RPS measurements were found to be suitable to determine both the recovery of the nanoparticles after filtration as well as subtle changes in their size distribution. Filtration through track‐etch membranes preserved the mean size of the nanoparticles while their recovery was affected by the size of the pore and coexistence of larger nanoparticle fractions in the sample. Centrifugal filtration resulted in the appearance of aggregates.

In situsilver nanoparticle coating of virions for quantification at single virus level

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