Question

What determines the elution order in sedimentation FFF?

Short answer

The order of elution for sedimentation FFF depends on the mass and size of components. The particles having small size and small mass eluted first and those with high mass and high density elutes last.

Step-by-step solution

Step 1. Given information

Determine the factor that determined the elution order in sedimentation FFF.

Step 2. Field flow fractionation method

The field flow fractionation method belongs to a family of analytical methods for separating molecules from colloids and solutions. This method involves the laminar flow effect that is linked with the concentration of analyte components which interacts with the physical field applied perpendicular to the flow of carrier liquid. The equipment is designed such that it contains a coiled channel that is fitted to a centrifugal basket.

Step 3. The elution order in sedimentation FFF 

The sedimentation FFF involves the application of force of gravity on the components or particles of the solution. The method applied technique of centrifuging such that the layers are formed of different thicknesses as the particle size and density varies. By allowing the solvent to flow the tube, which is perpendicular in direction to sedimentation, carries each component down the channel. Those particles forming the thickest layers are carried fast, especially at the center, where the flow velocity is fast. Hence, there is differential migration due to layer thickness.

From this, it is seen that those particles having small size and small mass eluted first and those with high mass and high density elutes last.