Eclipse™ AF4

The ultimate system for separating macromolecules, proteins, colloids, and nanoparticles.


The Eclipse® AF4 represents Wyatt Technology‘s fourth generation AF4 system and is the market-leading separation system using the Asymmetric-Flow Field-Flow Fractionation (AF4) technique. The Eclipse® AF4 solves the most difficult separation, fractionation and sizing tasks in the macromolecular and colloidal arenas. The advantage of AF4 over traditional SEC column chromatography is the ability to separate both soluable and colloidal components over a wide size range as well as sensitive and "sticky" samples (no stationary phase). Its resolution is similar to sedimentation equilibrium, but it surpasses even this benchmark-sizing tool when one considers its flexibility, speed, and ease of use.


The Eclipse™ AF4 is invaluable and indispensable in key areas of research and development in molecular biology, nanotechnology, and environmental analyses, including the separation and characterization of proteins and aggregates, liposomes, emulsions, viral particles, polysaccharides, nanoparticles, polymer latex particles, colloidal soil suspensions, humic substances, chemical mechanical polishing slurries (CMP), and many more.

AF4 Advantages:

  • Separates both soluble and colloidal components over a wide size range; especially unmatched powers in sub-micrometer range
  • Large dynamic range: from a few nanometers to a few micrometers
  • Rapid analysis: typically 10 to 30 minutes
  • Absence of shearing forces (no stationary phase; separation takes part in separation channel)
  • Ultra-high resolution separations, comparable to ultra centrifugation
  • Simplifies analysis by eliminating many time-consuming sample preparation steps
  • Adjustable and flexible separation ability: very efficient for complex samples
  • Direct injection: minimal sample preparation necessary
  • Interfaces with modern analytical methods like MALS, MALDI-TOF, etc.
  • Fractions can be collected and used for off-line analysis (with electron microscopy, MS, ICP-MS, ELISA etc.)

The Eclipse® is the world's most advanced AF4 system:

  • Fully automated, software controlled system with only one pump to generate detector flow, cross flow and injection flow. This innovative concept to generate all three flow streams from one main flow has been a breakthrough for the AF4 method!
  • One chassis contains all necessary electronic and fluid components, designed to stack with Wyatt Technology detectors (DAWN® , Optilab® , ViscoStar)
  • Eclipse® Chassis can be ordered in three versions: for aqueous solvents (biocompatible), for organic solvents and in a metal-free version
  • The Eclipse integrates into various market-leading HPLC packages, such as Agilent, Dionex and Shimadzu.
  • Independent, continuous measurement of the cross-flow and injection flow rate, which allows software controlled check on the system performance
  • Motor driven, software controlled needle valves for focus balance and injection flow rate control
  • Proprietary pressure sensor without dead-volume provides continuous read-out of channel pressure
  • High performance electronic controller inside the chassis (PLC- programmable logic controller) with TCP/IP communication to PC
  • Optimized lay-out of fluid connections minimizes tubing length and ensures easier serviceability
  • Eclipse chassis and electronics are protected against fluid damage through customized drip-pan with leak sensor
  • LCD-Display with system status information
  • CE classification surpasses laboratory standards for safety and emission and reaches industry grade
  • The Eclipse® is certified by TÜV Rheinland

Eclipse® Channel Design:


The Eclipse offers the most versatile separation channel technology. There are five different channel types plus the hollow-fiber-cartridge available to accommodate different requirements for sample load, analysis time, and resolution, as well as a wide choice of spacers and pre-cut membranes for all channel types. All channels have in common that the flow path is metall free, making them inert even in harsh conditions. The frit-inlet channel is shown with a cross-section displaying from bottom to top the lower PEEK-block, the frit, membrane and polycarbonate upper plate which is placed in an aluminum frame. The frit supporting the membrane is made from stainless steel, which is the most robust choice. As an option a metal free ceramic frit can be installed. All channels are easy to maintain. Replacing a membrane or cleaning the channel parts is straightforward, with just a few screws to tighten during the reassembly process.

  • Mini Channel (MC, 110 mm length)
  • Short Channel (SC 145 mm length)
  • Long Channel (LC, 275 mm length)
  • Semi-Preparative Channel (SP, 45 mm width, 275 mm length) 
  • Frit-Inlet Channel (FI-AF4)
  • Hollow-Fiber FFF Channel (HF5)

Turn-key Solutions:

  • The Eclipse separation system integrates the Eclipse chassis and channels (on the right) with high-quality HPLC components for liquid chromatography (on the left).

  • The Eclipse Flow-FFF allows to choose from a wide range of pumps, autosamplers, detectors and fraction collectors from the leading HPLC manufacturers Agilent, Thermo Fisher (Dionex), and Shimadzu.

  • Only one pump is needed to generate detector flow, cross flow, and injector flow by splitting the main flow delivered through the HPLC pump. Using only one pump results in a much improved signal-to-noise ratio because pump pulsations are reduced and operation is much easier.



  • Existing HPLC instruments can also be integrated easily with a new Eclipse system.

  • The Eclipse control is integrated in either Agilent ODS ChemStation or Dionex Chromeleon software allowing access to the extensive base of hardware which is supported by the two HPLC software packages.

  • Multi-Detection:
    The Eclipse® separation system is designed to integrate with Wyatt Technology’s complete range of unique multi-angle light scattering (MALS), dynamic light scattering (DLS), refractive index (RI) and viscometry (VI) detectors, ensuring highest sensitivity and optimum baseline quality.

Modular Approach:

If you would like to add FFF capability to your existing GPC/SEC column chromatography system, please
contact us. We can offer you an individual solution designed for your specific application and system requirements.


Do you want more information? We would be delighted to hear from you!