Online Laboratory Magazine

Centrifugal Field-Flow Fractionation - High Resolution Separation and Characterization of Bio-/Nanoparticles

CF 2000The advanced Postnova CF2000 Series is a powerful Centrifugal Field-Flow Fractionation (FFF) system specifically designed for the high-resolution separation and fractionation of nanoparticles.

The Postnova CF2000 Series is the first professional modular centrifugal FFF system available on the market allowing the simultaneous separation and sizing of nanoparticles.

Professional Modular System

The NovaFFF single software platform fully runs and controls the entire system from autosampler to detectors. The CF2000 integrates all combined technologies and impressively proves 30 years of expertise and leadership in Field-Flow Fractionation.

Its special design provides superior performance, better robustness, and higher flexibility than conventional particle sizing systems.

The CF2000 Centrifugal FFF enables high resolution particle separation and sizing in one single measurement, setting new standards and providing an excellent alternative to standard particle characterization methods.

Broad Separation Range

With its broad separation range, the CF2000 system is capable of separating smaller species, such as polymers and proteins from larger particles thus enabling separation of both nanoparticles and microparticles in one single run with high resolution. This not only includes the fractionation and characterization of well-established particulate samples such as silica, latex, TiO2, ZnO, Au and Ag particles, but is also applicable to highly complex samples such as environmental samples or drug delivery formulations.

Unlike standard particle sizing methods that work in batch mode Centrifugal FFF separates each particle fraction before sizing. This circumvents various disadvantages usually associated with stand-alone methods, particularly those based on light scattering, including for example low size resolution and a pronounced discrimination against smaller particle sizes in a polydisperse sample.

In addition, just like Flow FFF, there is no need for any special sample treatment as the particles can usually be directly injected without filtration, enabling the characterization of complex particulate systems without any significant sample alterations.

Particle Size and Density Separation

Based on the centrifugal FFF principle, the CF2000 Series system uses a centrifugal field as a driving force for the separation. Particles that are affected by this field are isolated by dynamic diffusion on the basis of both density and particle size. With this unique feature, different particulate materials exhibiting the same size, but different densities can be separated.

The ability to use various eluents and temperature programs facilitates further optimization of the separation process. The CF2000 is applicable to a wide range of complex particulate samples in the area of nanomaterial characterization and environmental analysis as well as food, agriculture and cosmetics.

Advanced Centrifugal FFF Detection

The CF2000 is available with various add-on modules such as autosamplers or fraction collectors as well as several dedicated FFF detectors, commonly dynamic light scattering (DLS), multi-angle light scattering (MALS), and UV-Vis detection, so that users can readily access the broad application range.

All Postnova FFF detectors and FFF modules are exclusively developed for FFF, and are optimized for use with the CF2000 Centrifugal FFF as well as other sub-techniques of the Postnova FFF platform. The CF2000 Series has also been developed to allow easy interfacing with advanced detection technologies from other instrument suppliers such as the Agilent 7900 and 8900 ICP-MS series.

This will allow all users to seamlessly incorporate the Postnova FFF technology into their current lab infrastructure.

Benefits of the CF2000 Series

  • High Resolution Separations: Centrifugal FFF has the ability to deliver true high resolution particle size separations. In comparison to other commercially available particle size analyzers, particle size in Centrifugal is not derived from mathematical assumptions and approximations, but by physical separation of single particulate fractions with very high resolution.
  • Broad Separation Size Range: With the CF2000 technology, small, medium, and large particles can be simultaneously separated and characterized in just one single measurement run while a significant discrimination against smaller particles by larger ones can be prevented, which is often a limitation of light scattering-based methods.
  • Separation under Native Conditions: The unique open Centrifugal FFF channel allows the use of any kind of eluent compatible with the sample particles enabling investigations under a large variety of distinct conditions. For example the agglomeration or dissolution rate of a nanomaterial with respect to the ionic strength or pH of the solvent, in which it is suspended, can be easily monitored thus helping to gain a deeper understanding of dynamic processes at the nanoscale.
  • Separation of Same Size Particles: Since Centrifugal FFF is able to separate both by density and size, particles of the same size, but different structures and chemical compositions, i.e. different densities, can be physically separated.
  • Flexibility and Connectivity: Thanks to its modular setup, the Postnova CF2000 Centrifugal FFF can be easily hyphenated with other available detection systems such as MALS, DLS, UV-Vis or ICP-MS. This can be performed both online and offline thus providing highest flexibility and performance in particle characterization.

Postnova Analytics GmbH
Max-Planck-Straße 14
D-86899 Landsberg

Tel.: +49 8191 985 688-0
Fax: +49 8191 985 688-99
Mail: Contact
Web: www.postnova.com