ideal speed(rcf) for eppendorf centrifuge

[larevalo]

Hi ,is anyone knows the ideal speed (rcf) for eppendorf centrifuge?We are preparing for validation performance for this centrifuge .It so happened when this equipment came to our section the supplier who installed it did not explain the importance of it.From the manual it doesnt say so only the time is mention which is 10 min.Our BioEngineer says rpm.What is the difference of rpm to rcf?

[heathervaught]

RCF stands for relative centrifugal force...basically, it takes into account the speed (rpm) and radius of the spin to determine the force that is applied to the object that is spinning. The formula is:

RCF = 28.38 x R x (rpm/10002)

Where R = radius in inches

And basically what you get is the number of Gs (the same type of G-forces that they talk about when an astronaut takes off in a space shuttle). Since the formula doesn't talk about time, often you will see "g x min" - you take the number of g's (calculated above) and multiply by the time that it is spinning. I am in the Component Lab, so our application of this was our plasma fractionator had a recommended 'g x min' value at which whole blood should be centrifuged. Using the radius of our centrifuges, I was able to determine what speed and time would get us within that range.

I am guessing that you are talking about centrifuging tubes...if you look in the package insert for the reagents or tests you will perform, there should be a section that discusses sample preparation and how the tubes should be spun. Start from there.

Heather

Edited June 9, 2008 by heathervaught
clarification