Eclipse AF4

Eclipse AF4

Versatile separations of polymers, proteins, colloids, and nanoparticles.

Uniquely Versatile

Flow Field-Flow Fractionation is a uniquely versatile means of size-based separations, capable of fractionating and characterizing proteins and aggregates, liposomes, emulsions, viral particles, polysaccharides, nanoparticles, polymer latex particles, colloidal soil suspensions, chemical mechanical polishing slurries, and many more - with no stationary phase and almost no shear.

AF4 Techniques

The Eclipse™ AF4 supports all AF4 techniques except Hollow-Fiber Flow Field-Flow Fractionation (HF5), which is covered by the Eclipse DualTec. However, the Eclipse AF4 supports the fritless AF4 channel which prevents the difficulties encountered by certain samples prone to aggregation at the relatively high concentrations typical of the AF4 focusing step. It also supports the semi-preparative channel.

The Eclipse AF4 combines with a DAWN MALS detector and Optilab dRI detector to solve the most difficult separation, fractionation and sizing tasks in the macromolecular and colloidal arenas including polymers, biotechnology, pharmaceuticals, nanotechnology and environmental analysis.


The advantage of AF4 over traditional SEC column chromatography is the ability to separate both soluble and colloidal components over a wide size range as well as sensitive and "sticky" samples, since there is no stationary phase. AF4 even overcomes the non-ideal behavior exhibited by large, branched polymers that elute abnormally on GPC columns. The Eclipse provides resolution similar to that of analytical centrifugation (AUC) but surpasses even this benchmark tool when one considers its flexibility, speed, and ease of use.


Common solution-based methods for determining the size and size distributions of nanoparticles, such as batch dynamic light scattering (DLS) and nanoparticle tracking analysis (NTA), cannot offer the resolution, statistical confidence and absolute accuracy of a true separation-based technique that incorporates MALS and DLS downstream detection.

FFF-MALS and FFF-DLS performed with an Eclipse AF4, DAWN and an embedded WyattQELS DLS detection module offer excellent resolution and accuracy in analysis of size distributions. Particle counts and sizes of viruses and virus-like particles estimated by FFF-MALS match closely TEM-based counts.

Key benefits of FFF with a Wyatt Eclipse:

  • Robust separation of macromolecules and nanoparticles from 1 nm to 1000 nm with excellent resolution
  • No stationary phase - open channel separation with minimal shear and surface interactions
  • Versatile choice of separation channels, permitting sample loads from µL to mL, including semi-preparative FFF
  • Optimize separation methods to enhance resolution or size range simply by adjusting flow ratios, even programmatically during a run
  • Fractions can be collected and used for off-line analysis (with electron microscopy, MS, ICP-MS, ELISA, etc.)

... and of the Eclipse AF4:

  • Typical analysis times 10 - 30 minutes
  • Utilize the fritless column for aggregation-prone samples
  • Make use of the highest quality HPLC pumps and autosamplers from Agilent, Shimadzu, Thermo, or Waters
  • Integrate with your favorite HPLC software from Agilent, Dionex or Shimadzu
  • Couple to ICP-MS for elemental analysis of nanoparticles per size bin

The Eclipse is the world's most advanced AF4 system

  • Fully automated, software controlled system with only one pump to generate detector flow, crossflow 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
  • Chassis can be ordered in two versions: for aqueous solvents (biocompatible) and for organic solvents
  • The Eclipse integrates into various market-leading HPLC packages, such as Agilent, Dionex and Shimadzu
  • Independent, continuous measurement of the crossflow 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 layout 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 displays system status information
  • CE classification surpasses laboratory standards for safety and emission and reaches industry grade
  • The Eclipse is certified by TÜV Rheinland

Eclipse AF4 Channel Design

Eclipse Channels The Eclipse AF4 offers the most versatile separation channel technology. There are four different channel types 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 except the frit-inlet channel have a metal-free flow path, making them inert even in harsh conditions. In the frit-inlet channel, 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.

  • 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 (Fl-AF4)

Integration with Wyatt Technology instruments and market-leading HPLC packages

Eclipse Stack

  • The Eclipse separation system is designed to integrate with Wyatt Technology's range of unique light scattering and dRI detectors, ensuring highest sensitivity and optimum baseline quality.
  • The Eclipse operates in conjunction with Agilent, Shimadzu, or Dionex chromatography components. You can stay with your current HPLC software platform and run the Eclipse with the familiar interface you already know.
  • Only a singe HPLC pump is needed to generate detector flow, crossflow, and injector flow, accomplished 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 balanced between flows, so operation is much easier.


On-Line MALS

DAWN - The most sensitive MALS detector available, anywhere. Incorporates detectors at 18 angles to determine molar masses from 200 Da to 1 GDa and radii from 10 to 500 nm. Heated/cooled option -15°C to +150°C.

The DAWN offers advanced options such as fluorescence or polarization filters and a 785 nm laser.

miniDAWN - Second only to the DAWN in sensitivity. Incorporates detectors at 3 angles to determine molar masses from 200 Da to 20 MDa and radii from 10 to 50 nm. Ambient only.


Optilab - A unique on-line differential refractometer for measuring concentration of any macromolecule, regardless of chromophores.


WyattQELS - A dynamic light scattering (DLS) module which integrates inside the DAWN or miniDAWN to provide simultaneous DLS measurements in the same scattering volume. The optical fiber replaces any one MALS detection angle.

Complete FFF-MALS systems

Eclipse DualTec

  • 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 you to choose from a wide range of pumps, autosamplers, detectors and fraction collectors from the leading HPLC manufacturers Agilent, Dionex, and Shimadzu.
  • Only one pump is needed to generate detector flow, crossflow, 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 Agilent ChemStation, Agilent OpenLAB, Thermo (Dionex) Chromeleon, or Shimadzu LCsolution software allowing access to the extensive base of hardware which is supported by the HPLC software packages.
  • The Eclipse DualTec 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.

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.

Separation range  
   Standard mode 1 nm to 1000 nm, depending on specific sample properties and separation channels
   Steric mode Approximately 1 µm to 10 µm, depending on specific sample properties and separation channels
   Crossflow rates Channel dependent:
0.04 to 3.3 mL/min standard
0.07 to 6.6 mL/min
0.1 to 8.3 mL/min
   Maximum total flow rate 10 mL/min (crossflow plus detector flow rate)
Maximum channel pressure 30 bar, software overpressure shut-down
Spacer thickness Set of spacers with 250, 350 and 490 µm; each thickness comes in two different channel widths
Pre-cut  membranes Polyether Sulfone: 1, 3, 5, 10, and 30 kDa cut off
Cellulose Triacetate: 10 kDa cut off
Regenerated cellulose: 5, 10, and 30 kDa cut off
Eclipse channels Short SC: 153 mm e.l.
Long LC: 246 mm e.l.
Semi-Prep SP: 246 mm e.l.

SC, LC maximum spacer width 22 mm
SP maximum spacer width 44 mm
Eclipse chassis Two proprietary pressure sensors 0 to 30 bars, no dead volume
LiquiFlow flow meter for injection path 0.01 to 1 mL/min
CoriFlow flow regulator for crossflow control
Leak sensor
Motorized needle valves for injection and focus
   Standard version Rated for aqueous solvents and alcohols
Guaranteed corrosion resistant from pH 2 to 12

Aqueous channel: PEEK, aluminum cover with polycarbonate insert, Viton, stainless steel
   Organic option Rated for organic solvents (e.g., THF, toluene, etc.)
Stainless steel tubing
Additional vapor sensor with interlock output

Organic channel: PEEK, Kalrez, aluminum, stainless steel
   Display Front panel LCD
   Inputs Autoinject In, Analog In
   Outputs Autoinject Out, Analog Out, Detector Zero, Start Pump, Agilent pump interlock (organic version only)
   Communication Ethernet (TCP/IP)
Software Integrated in Agilent ChemStation, Dionex Chromeleon, and Shimadzu LCsolution
Dimensions 64 cm (L) x 36 cm (W) x 25 cm (H)

Host PC requirements may be found in Computer Requirements.

Specifications subject to change without notice.

Other FFF Instruments

Eclipse DualTec

Eclipse™ DualTec™
- Tip-injection FFF fluidics control system that integrates with your HPLC pump and autosampler to provide all the advantages of FFF without losing SEC capabilities. Supports switching between any two of AF4, HF5 and SEC.