Sizing Nanoparticles and Macromolecules in Liquids using an Electrospray and Scanning Mobility Particle Sizer™ Spectrometer
ES-SMPS and ES-DMA (a.k.a. macroIMSTM Macroion Mobility Spectrometer, GEMMA, ES-IMS, nES‑GEMMA) are acronyms coined by researchers to describe an Electrospray Aerosol Generator (EAG) paired with a Scanning Mobility Particle (SMPS) Spectrometer used to perform rapid, high resolution sizing of nanoparticle colloids, proteins and other macromolecules.
The fundamental measurement behind the ES-SMPS technique is Differential Mobility Analysis. Briefly described, the EAG is used to aerosolize the colloidal suspension (similar to ESI-MS), and then particles are sized via their electrical mobility (ability to traverse an electric field) resulting in a measurement of electrical mobility diameter (EMD) which is a fundamental function of particle size.
The ES-SMPS technique is frequently chosen by researchers over more conventional techniques and its use is increasingly widespread. The National Institute of Standards and Technology (NIST) & the National Characterization Laboratory (NCL) issued a Joint Assay Protocol, “PCC-10: Analysis of Gold Nanoparticle by Electrospray Differential Mobility Analysis (ES-DMA)” which details a protocol for size analysis of liquid born gold nanoparticles via ES-SMPS.
Useful Information via ES-SMPS
- Size Distributions of Nanoparticles in Solutions
- Molecular Mass of Proteins and other MacroMoleculesInsight into Colloidal Kinetic
- Kinetic Evaluations of Aggregation Behavior
- Investigations of Nanoparticle Dissolution
- Surface Density and Thickness of Nanoparticle Coatings
Benefits of ES-SMPS
- Nanoparticle Size Accuracy
- Nanoparticle Size Resolution
- Accurate Measurement of Multimodal Size Distributions
- Single Particle Sizing
- Sensitivity to Small Changes in Size
- Measurement of Molecular Mass/Molecular Weight (MW)
- High Sensitivity
- High Precision and Repeatability
- Small Sample Volume (~20mL)
- Large Measurement Samples
- Fast measurement times
- First Principle Measurement
- Independent of Optical Properties of Material or Solution
- Independent of Sample Temperature
- Well Understood Technology
Refer to Application Note ES-001 and TSI's ES-SMPS bibliographies for more information.
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