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Updated: Aug 27, 2025

Measurement of Particle Size Distribution in Turbid Solutions by Dynamic Light Scattering Microscopy

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Published on: January 9, 2017

Number Concentration Measurements of Polystyrene Submicrometer Particles.

Paul C DeRose¹, Kurt D Benkstein², Elzafir B Elsheikh¹

¹Biosystems and Biomaterials Division, National Institute of Standards and Technology (NIST), Gaithersburg, MD 20899, USA.

Nanomaterials (Basel, Switzerland)

|September 23, 2022

Summary

This summary is machine-generated.

Accurate submicrometer particle measurements require reliable standards. This study found significant variations in number concentration measurements across different techniques, highlighting the need for standardized calibration methods.

Keywords:

NIST bead calibration concentration diameter flow cytometry nanosphere number reference materials standards submicrometer

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$Studying Soft-matter and Biological Systems over a Wide Length-scale from Nanometer and Micrometer Sizes at the Small-angle Neutron Diffractometer KWS-2$

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Published on: May 20, 2014

Area of Science:

Nanotechnology
Metrology
Analytical Chemistry

Background:

Increasing number of techniques for submicrometer particle measurement.
Need for submicrometer particle standards to enhance accuracy and reproducibility.
Current methods show variability in measuring particle number concentrations and size distributions.

Purpose of the Study:

To assess the accuracy and reproducibility of different techniques for measuring submicrometer particle number concentrations.
To evaluate the suitability of polystyrene spheres as submicrometer particle standards.
To propose a protocol for certifying SI-traceable number concentration standards.

Main Methods:

Measurement of number concentrations and diameters of 100 nm, 200 nm, and 500 nm fluorescently labeled polystyrene spheres.
Utilized seven different measurement techniques.
Three techniques were employed to determine SI-traceable number concentration values.

Main Results:

Diameter measurements agreed within 20% across techniques.
Number concentration measurements varied by as much as a factor of two.
Identified significant discrepancies in particle number concentration determination.

Conclusions:

Submicrometer particle standards are crucial for instrument calibration and inter-technique comparability.
A consensus approach using SI-traceable values is proposed for certifying particle number concentration standards.
Standardization is essential for reliable submicrometer particle metrology.