# To get clear plasma out of a minute particle (such as fibrin), is it necessary to vortex sample before centrifugation? [closed]

I'm going to analyse plasma samples that contain a lot of fibrin. It is necessary to centrifuge the samples to be able to pipette the plasma. After the samples are centrifuged I can't vortex them because then I mix everything again and it wont be possible to pipette. Now I wonder whether it is necessary to vortex them before I centrifuge them. I don't think so because during centrifugation particles will anyway be separated by density. Or am I wrong? And in that case why? Appreciate your thoughts!

• Are you talking about plasma or serum? Did you already separate either from blood sample? You need to include these specific info in your question. – Mathew Mahindaratne Feb 10 at 17:04
• I'm voting to close this question as off-topic because it doesn't seem to be about chemistry. – Mithoron Feb 10 at 17:55
• @Mathew Mahindaratne it is plasma and yes it is allready separated from erytrocytes. Sorry for leaving out information! – Anna Feb 10 at 19:50
• @Mithoron It is about how chemicals separate, do you know a more suitable forum for this type of question? – Anna Feb 10 at 20:00
• Visible solid fiber particle (e.g., fibrin) will separate in higher speed centrifugation by gravity (not really by density). If your analysis is based on density gradient, you should use ultra-centrifuge (rpm is about $1.0 \times 10^5$ or higher). – Mathew Mahindaratne Feb 10 at 20:00