Protein Characterization POSTnova - Spincotech

High-Resolution Analysis of AAV8 Vectors by Multi-Detector Asymmetrical Flow Field-Flow Fractionation (MD-AF4)

Application Note

AAVs are promising gene therapy vectors but require precise characterization, and MD-AF4 provides a high-resolution, label-free approach to assess particle size, capsid content, titer, and impurities, delivering reliable results for AAV8 analysis and development.

Field-Flow Fractionation

Postnova Analytics offers the gold standard in field-flow fractionation. Our unique analytical characterization platform is the premier solution for the advanced analysis of nanoparticles, proteins, and macromolecules.

60 Years of Field-Flow Fractionation – A Technology That is Shaping the Future of Separation Science

Postnova is the inventor and leader in Field-Flow Fractionation and innovator in Light Scattering technology, offering solutions used by leading scientists in laboratories worldwide. Our instruments are crucial for the Biopharma industry to fight and cure diseases, in Material Science to develop new high-tech nanomaterials and polymers and in Environmental Research to provide nothing less than solutions to save the planet.

How does Field-Flow Fractionation Work?

Core Principle

AF4 separates particles based on size (hydrodynamic radius) using two flows inside a thin channel:

Channel flow → pushes sample forward toward the outlet
Crossflow → pushes sample downward toward a semi-permeable membrane

Because of diffusion

Small particles diffuse farther away from the membrane → move faster → elute earlier
Large particles stay near membrane → move slower → elute later

So separation occurs by diffusion vs. crossflow balance, not by interaction with a column packing.

How the Separation Happens (Step-by-Step)

Injection – Sample enters channel
Focusing – Flow from both sides concentrates sample into a thin band
Relaxation – Crossflow pushes particles toward membrane
Elution – Channel flow carries particles out based on size

FFF Principle

FFF principle 3D

Our Solutions

Biopharmaceutical

Proteins
Biopolymers
Nanoparticles
Microparticles

Polymers

Polymers
Nanoparticles
Microparticles

Environmental

Biopolymers
Nanoparticles
Microparticles

Food-Agro-Cosmetics

Proteins
Biopolymers
Polymers
Nanoparticles
Microparticles

our expertise

The Postnova Advantage

Postnova Analytics combines advanced Field-Flow Fractionation (FFF) with multi-detector technologies to deliver high-resolution characterization of nanoparticles, proteins, polymers, extracellular vesicles, and complex biologics. Its column-free separation approach enables gentle, accurate, and reproducible analysis across a broad size range for advanced research and biopharmaceutical applications.