Sentence:  They were then <WSD>centrifuged</WSD> at 59780 rpm for 35 to 80 min at 20 ` C in a Spinco model E ultracentrifuge at a protein concentration of 1.00 to 1.25 % . 
Meaning of the word marked with <WSD> tags:  rotate at very high speed in order to separate the liquids from the solids