nCS1 by Spectradyne
Particles size and Concentration
Microfluidic Resistive Pulse Sensing (MRPS) uses electrical sensing to measure the diameter of each particle as it passes through a nanoconstriction, providing real-time sizing and concentration information.
- Resistive pulse sensing and size measurements of individual nanoparticles in fluid
- Particle size distribution with absolute concentration
- Particle size analysis range: 50 nm to 10 μm in diameter
- Concentration range: approx. 1E+6 — 1E+11 particles/mL
- Max particle detection rate: approx. 10,000 particles/s
- Nanoparticles of any material type (transparent & opaque, conducting & insulating)
Resistive pulse sensing
A single nanoparticle increases the electrical resistance of the suspending fluid as it passes through the nanoconstriction, giving rise to a brief voltage pulse. The size of the pulse is proportional to the nanoparticle volume; the amplitude and duration of the pulse gives the particle diameter and the mean velocity, a method known as resistive pulse sensing. Longer measurements accumulate many pulses.
Software-based analysis is used to combine measurements of a large number of particles into a histogram of particle diameters, with the vertical scale in units of nanoparticle concentration. After removing the dependence on the width of histogram binning, the resulting Concentration Spectral Density (CSD) has units of nanoparticles per unit volume per unit diameter (e.g., particles · mL-1 · nm-1). Because of the fast measurement capability of the nCS1, good statistics can be obtained in a few seconds.