Compare with other particle size analyzer technologies

What's the best way to determine what's in your sample?

Particle size analysis instruments are not created equal:

  • Dynamic light scattering (DLS)
    • Does not measure every particle: This is an ensemble technique
    • Does not measure concentration
    • Often gives spurious results, with peaks in population that are not there
  • Optical tracking
    • Limited concentration range, often requiring dilution
    • Very slow to accumulate statistically significant results
    • Relies on high index contrast, making biological particles challenging
  • Resistive pulse sensing: Spectradyne's nCS1TM
    • Measures every particle individually
    • Can measure large concentration range without dilution
    • Accumulates statistically significant counts in a few seconds

DLS and optical tracking fail to resolve the four different diameters in the sample, while Spectradyne's nCS1TM accurately reproduces the actual synthetic mixture.

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How to analyze nanoparticles

Resistive pulse sensing

resistive pulse sensing

Are you looking for a reliable method to analyze the nanoparticles in your sample? There are two distinct approaches to detecting and measuring the size of nanoparticles in solution, optically-based methods and electrical methods. The only direct way to individually detect and directly measure the size of nanoparticles is using resistive pulse sensing, as developed by Spectradyne LLC. In this method, nanoparticles are made to flow through a microfluidic circuit that includes an engineered nanopore. Each individual particle is detected and its size measured, using a technique that is the gold standard for whole blood cell counting. Spectradyne's team of engineers has brought this clinical standard to the world of nanoparticle analysis, bringing unprecedented precision and accuracy to the world of nanoparticle analysis.

Spectradyne's novel implementation of resistive pulse sensing yields direct diameter measurements of each and every particle, and through its calibrated flow rate measurement, also provides accurate concentration information as a function of particle diameter. This unique combination of high precision individual particle measurements and calibrated concentration makes Spectradyne's nCS1 a unique player in the field of nanoparticle analysis.

Other methods


Optically-based analysis methods, by contrast, rely on the scattering of light by the nanoparticles of interest. These optically-based techniques do not in fact directly measure the sizes of particles, but instead rely on complex mathematical formulas with many hidden assumptions in order to generate estimates of particle diameter. The amount of light scattered depends strongly on the contrast of the optical index of refraction of the nanoparticles, in comparison to the suspending medium; as a result, particles with different indices will yield different results. Biologically-based nanoparticles often have an index so close to that of water that they are essentially invisible! In addition, the intensity of scattered light varies as the sixth power of the diameter, so that results are often strongly skewed towards these larger particles, making reported distributions inaccurate and unreliable. Furthermore, for the most popular method, known as dynamic light scattering or DLS, the concentration of any particular diameter particle, or of the particle solution as a whole, is not even accessible!

Learn more about Spectradyne's innovative electrical nanoparticle analysis technology!

Read our head-to-head comparison application note, or send an email to

High resolution nanoparticle size analysis

Spectradyne is where every particle countsTM

Watch a video of the nCS1TM in action!

The nCS1TM nanoparticle analyzer


Spectradyne's nCS1 instrument provides a unique platform for the rapid quantitative measurement of nanoparticles in solution. The method used to measure nanoparticles is electrical in nature, so does not rely on an optical index contrast to distinguish particles from their suspending medium. The instrument measures individual nanoparticles and rapidly accumulates statistically-reliable distributions of particle sizes with quantitative concentration information. This unique capability separate the nCS1 from any other instrument on the nanoparticle analysis marketplace.

Watch a video of the nCS1 in action!

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