Do analytical ultracentrifuge (AUC) rotors differ from those for a preparative centrifuge?

Yes. AUC rotors are designed to address additional considerations, such as:

Light passage

AUC rotors are designed so light can pass through a sample, generally from top to bottom. A small lip at the bottom of the well holds the sample cell in place.

Overspeed disk

To prevent damage, the overspeed disk allows the system to determine the maximum rated speed of the rotor and prevent it from spinning faster than that maximum.

Timing magnet

This is embedded in the overspeed disk. A pickup device in the system senses when the magnet passes over and generates a pulse that represents a known time. The AUC uses this pulse to synchronize the rotor speed with the flash of the light source.