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Questions tagged [centrifugation]

a process which involves the application of the centrifugal force for the sedimentation of heterogeneous mixtures with a centrifuge, and is used in industrial and laboratory settings. Use this tag in questions related to instruments that exploit this technique, or fields of biology in which this technique is applied.

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How to isolate a high proportion of available helminth ova from animal faeces/feces without damaging them?

I need to isolate large numbers (tens to hundreds of thousands) of cat (and later dog) hookworm ova from cat/dog faeces. I have a centrifuge, and various sieves with pore sizes of 20, 63, 75, 106, ...
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Centrifuge after sonication

I follow a protocol to get protein from E.coli cells after sonication. I used to grow 6 litres of large cultures and add IPTG to express the protein. I centrifuge for 10 mins at 8,000 rpm and get the ...
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What prevents a density gradient made of sucrose from mixing through diffusion?

Based on what I've read, density gradients are used to facilitate separation in ultracentrifugation and prevent convective mixing of the molecular species from different locations in the gradient. But ...
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Is there a way to remove hemoglobin from pig kidney homogenate without deactivating enzymes?

I would like to measure different enzyme activities in centrifuged pig kidney homogenate. I get out of range errors at 450 nm. The samples are still reddish after centrifugation. Is there a way to ...
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optimization of density gradient centrifugation

I'm trying to isolate a ~320kD protein (in oligomeric form) using density gradient ultra centrifugation technique. Can any one tell me that what gradient (sucrose or glycerol or trehalose or etc) I ...
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What is the sedimentation coefficient of Mycoplasma?

I have attempted to find the sedimentation coefficient of a number of bacterial species, namely E. coli and a number of Mycoplasma species, but they seemed to be rather elusive in the literature. If ...
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Estimating RPM to RCF in Methods from Older Papers

I'm attempting to replicate a cell biology method from a 1958 Laboratory Investigation paper. The protocol is for the isolation of an extracellular matrix protein, and a key step is a centrifugation ...
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What's the physical meaning of Svedberg unit?

Sedimentation coefficients, using a centrifuge, are expressed using Svedberg unit (symbol S, sometimes Sv). Wikipedia states that $S = 10^{-13}$ sec but I also saw in a book that actually $S = 10^{-13}...
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Changing time and rpm of centifuge

Inspired by this question, I want to ask a question about centrifugation. Suppose a protocol says : 10 min at 2500 rpm . Can we instead centifuge for 5 min at 5000 rpm or 20 min at 1250 rpm ?