The meaning of “×g” in centrifuge parameters

Release time:

2014-04-22

Overview:

For example: 5000×g means 5000 times the acceleration due to gravity.

In general, low-speed centrifugation is typically expressed in terms of rotational speed “rpm,” while high-speed centrifugation is expressed in “g.” When calculating the relative centrifugal force acting on particles, it’s important to note that the distance “r” from the centrifuge tube to the center of the rotation axis varies; consequently, the position of the settling particles within the centrifuge tube differs, and so does the centrifugal force they experience.

Therefore, when reporting ultracentrifugation conditions, the multiple of Earth’s gravitational acceleration, “×g,” is typically used instead of revolutions per minute (rpm), as it more accurately reflects the centrifugal force experienced by particles at different positions within the centrifuge tube and its dynamic variations. The centrifugal force data usually refer to the average value (RCFa v)—that is, the centrifugal force at the midpoint of the centrifuge tube.

For example: 5000×g means 5000 times the acceleration due to gravity.

× means multiplication; it means a multiple.

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