Table 1 Commonly used experimental techniques to characterize NP size
From: Engineered nanoparticles interacting with cells: size matters
Technique | Advantages | Limitations |
|---|---|---|
TEM | Direct visualization, high resolution | NP aggregation during sample preparation, electron beam damage, preference for electron-dense atomic species |
DLS | Size distribution information available, fast, simple | Signal dominated by larger NPs, interference from luminescent species |
NTA | Real time analysis, particle-by-particle measurement | Suitable to a certain size range, interference from luminescent species |
FCS | High sensitivity, small sample volume, particle-by-particle measurement | NPs need to be luminescent, sensitive to aggregates |
AFM | High size resolution, 3-D profile | Slow speed, limited scanning area |
Absorption spectra | Simple, fast | Applicable to plasmonic (Au, Ag) and semiconductor (CdSe, CdTe) NPs |
Analytical ultracentrifugation | Size distribution information available, high size resolution | Density of NPs needs to be known, long measurement time |