Gain Deeper Insights with High-Precision Zeta Potential Measurement

Achieve unmatched accuracy and precision in measuring the zeta potential and size of biological particles with tunable resistive pulse sensing (TRPS). By individually analysing each nano-sized particle, TRPS surpasses traditional dynamic light scattering instruments, providing superior resolution and deeper insights for applications in nanomedicine, drug delivery, and extracellular vesicles.


Beyond Averages: Measure Individually

Obtain an accurate view of charge distribution through particle-by-particle zeta potential analysis.

Analyse Zeta Potential and Size Concurrently

Access simultaneous measurements of zeta potential and size, allowing you to consider both charge and aggregation insights when assessing sample stability.

Characterise Your Samples with Confidence

Rely on standarised protocols and the high-resolution precision of TRPS measurements to confidently compare your samples.

What is Zeta Potential?

Zeta potential is an important characterisation method used to gauge a particle's surface charge and colloidal stability.  

Defined as the electrical potential at the slipping plane of the interfacial double layer, zeta potential represents the magnitude of the electrostatic repulsion or attraction between particles.

Zeta potential analysis is used to assess sample and product stability across a range of applications involving nano-sized particles, including in nanomedicine and extracellular vesicle research.

Schematic representation of zeta potential, adapted from Williams 2016. DOI: https://doi.org/10.1007/978-3-662-44324-8_612

With tunable resistive pulse sensing (TRPS), size and zeta potential are measured simultaneously on a single-particle basis.

How Does TRPS Measure Zeta Potential?

Tunable resistive pulse sensing (TRPS) technology is based on the analysis of resistive pulse signals which occur as nanoparticles pass through a size-tunable nanopore.

Each pulse signal, known as a blockade, provides information on the size and zeta potential of an individual particle.

Blockade duration and magnitude is assessed as a function of both voltage and pressure, calibrated against standardised particles with a known size and zeta potential.

Distinguish Nanoparticle Subpopulations with High-Resolution Insights

The high resolution of TRPS measurements allows for effective sample comparison, enabling the detection of subtle shifts in particle stability.

By simultaneously measuring both size and zeta potential, TRPS provides the granularity needed to identify distinct subpopulations within heterogenous, multimodal samples.

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Zeta potential vs particle size of bare polystyrene (CPN100), carboxylated polystyrene particles (CPC70, CPC100), magnetic particles (Bio-Adembeads) and magnetic particles modified with DNA.

Subpopulations were clearly distinguished when analysed both separately (circles) and together (triangles).

Adapted from Vogel et al. (2017). High-Resolution Single Particle Zeta Potential Characterisation of Biological Nanoparticles using Tunable Resistive Pulse Sensing. Scientific Reports 7, 17479. https://doi.org/10.1038/s41598-017-14981-x

A comparison of zeta potential data when measured with TRPS (top) and PALS (bottom). The bimodal sample contained low-charged 380 nm bare polystyrene particles and highly charged 400 nm carboxylated polystyrene particles.

Obtain Valuable Single-Particle Measurements, Not Averages

TRPS technology delivers precise, single-particle characterisation, offering critical insights for optimising production protocols, comparing storage conditions for extracellular vesicles, and refining lipid nanoparticle formulations.

This unique capability of TRPS is highlighted in a comparison with phase analysis light scattering (PALS) analysis. While PALS provides an average value, TRPS can distinguish between two distinct particle populations, offering more detailed and actionable insights.


Redefine Zeta Potential Measurement with the Exoid's Single-Particle Precision

The Exoid's clean user interface provides guidance throughout the process of measuring zeta potential with tunable resistive pulse sensing technology.

Using specialised nanopores, you can measure the size and zeta potential of negatively charged particles in defined size brackets between 80 and 400 nm.



The Exoid: Successor of the qNano Gold

The Exoid is Izon’s Tunable Resistive Pulse Sensing (TRPS) system. Unlike with the qNano Gold, where parameters were adjusted manually, pressure, voltage and pore stretch are adjusted directly from your Exoid-connected device. Significant hardware improvements reduce noise levels significantly over the qNano, meaning that smaller particles can be measured more reliably. The Exoid also has a clean user interface which provides guidance throughout the setup and measurement process

Learn more about the Exoid

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