Rotor Selection Guide

For each ultracentrifuge type there is a range of interchangeable cores available that fit the supplied rotor assembly, to allow the user to create different separation capabilities within one ultracentrifuge system.

graph icon

The Alfa Wassermann Advantage

Linear Scale Rotor Cores

The linear scalable ultracentrifuge rotors from Alfa Wassermann are unique among ultracentrifuges. They are designed with scalable applications in mind to allow the user to generate the same separation profile at different process volumes when using AWST ultracentrifuge systems. Having this capability to go from research to pilot scale to full scale production results in enormous cost savings. This patented linear scale core technology enables a direct scale up of separation between the research scale Promatix 1000™ to the PKII and to the KII manufacturing scale Ultracentrifuge.

Once a series of separation parameters (such as volume, path length, centrifugal force and run time) have been proven to work the process can be fully scaled up or down.  There is no need for further alterations or extensive testing and re-validation, which results in significant cost savings. A 14 fold scale down is achievable through this cost effective and labor saving approach.

Each ultracentrifuge is supplied with a rotor assembly which can be used at speeds up to 40,500 rpm. The rotor cores are interchangeable to create different separation capabilities within one ultracentrifuge system. KII rotor volumes range up to 8.4 liters and PKII rotor volumes to 4 liters.

The KII, PKII and Promatix 1000™ Ultracentrifuges are used to perform purifications and separations on a continuous or batch basis – with or without density gradients – with a range of techniques, including:

. Density gradient ultracentrifugation
. Rate zonal separation
. Isopycnic banding
. Pelleting
. Clarification

Contact Us


Our Mission

To be the supplier whose singular purpose is the support of bioprocess and pharmaceutical industries by providing expertise in continuous flow UCF separation applications and now fluid handling solutions.

Contact Us


Alfa Wassermann Inc . 4 Henderson Drive
West Caldwell . NJ 07006 . USA

Telephone +1 800 220 4488
Fax +1 973 276 0383


Alfa Wassermann B.V. Lorentzlaan 5
3401 MX IJsselstein . Netherlands

Telephone +31 348 487 300
Fax +31 348 433 000

Contact Us