3263 - Why are samples centrifuged at 4°C after the addition of chloroform when using the RNeasy Plus Universal Mini Kit?

Phase separation by centrifugation at 4°C, after adding chloroform and gDNA Elimiator solution to the samples, minimizes genomic DNA contamination. Subsequent centrifugation steps with RNeasy spin columns have to be carried out at room temperature to prevent buffer salt precipitation and to guarantee optimal binding of RNA to the columns.  This then ensures the highest RNA yields possible.