Liquid Nanoparticle Sizer: How It Works
Liquid NanoParticle Sizer User Guide
4
Version 1.0.1
How the Liquid NanoParticle Sizer Works
The LNS is a fully integrated three-stage system incorporating a NanoParticle
Nebulizer (NPN), an Annular Flow Ion Mobility Classifier (AFIMC) and a
Fast Condensation Particle Counter (Fast CPC) to measure particles as small
as 5 nm.
A sample of a liquid colloid suspension is introduced to the NPN through an
online direct-feed method or using a peristaltic pump or autosampler. The
sample can be diluted before introduction to reduce coagulation time and
minimize contamination. The sample is nebulized and the largest droplets,
which may contain multiple particles, are removed. The nebulized sample is
heated to evaporate the water leaving an aerosol of particles suspended in
the carrier gas. The aerosol is then combined with clean, dry air. Up to 1.5
L/min of dry aerosol flow can be drawn from the aerosol outlet.
The aerosol particles are electrically charged using a safe and reliable soft x-
ray charger. The AFIMC sorts the particles by size in an electric field and is
capable of classifying particles from 5-500 nm in size. Using varying electric
field strength, the AFIMC systematically selects particles of a narrow size
band and passes them on to a Fast CPC.
The Fast CPC immediately counts the concentration of particles in selected
size bands and detects individual particles with a dynamic concentration
range over three orders of magnitude. Unlike competing particle
measurement technologies, the LNS provides actual, not relative, particle
concentration.
Figure 1: Aerosolization coupled with Ion Mobility Spectrometry to measure
nanoparticle size distribution in liquid.
