Analysis and Characterization of Manufactured Nanoparticles in Aquatic Environments - Environmental and Human Health Impacts of Nanotechnology - page 214

Irregular particle Equivalent spherical size measure Applies to method f

Hydrodynamic
diameter a

Flow-FFF, DLS, NTA

Equivalent spherical
volume diameter

Sed-FFF (for known
density), LIBD,
Electrozone sensing,
Centrifugation

Buoyant Mass Sed-FFF *V

∝ ∆ δ

Equivalent spherical
mass diameter

MS b

Microscopy c Equivalent spherical

max length diameter

Equivalent spherical
min length diameter

Equivalent spherical
projected area
diameter

Equivalent spherical
specifi c surface area
diameter

BET with known
density

Equivalent spherical
pore size diameter

Particle fi ltration d

Root mean square
radius of gyration e

SLS

This example value: 4 Aspect ratio: the longest

dimension divided by
the shortest

Microscopy,
Combination of light
scattering methods or
different FFF methods

a Calculated from the measured diffusion coeffi cient, using Stokes-Einstein equation
b To calculate size from mass assume a certain structure
c Can be derived manually or by image analysis softwares
d Filter pore size often defi ned as maximum size (not average size) that penetrates fi lter
e Mean square distances from center of mass of point masses within the particle
f For method abbreviations, see text.