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Cristina Basu ● 2008-04-21 20:06 (6288 d 19:36 ago) Posting: # 1783 Views: 8,613 |
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Hello! Could you tell me how could I calculate the parameters (rpm, temperature, time) of centrifugation of the whole blood in order to separate plasma? How could I validate them? Is it necessary to demonstrate the recovery of the analyte from blood or the stability of analyte in the whole blood at the chosen temperature for the chosen centrifugation time or both of them? Thank you very much! |
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sudeshnamandal1 ☆ India, 2008-04-22 08:58 (6288 d 06:44 ago) @ Cristina Basu Posting: # 1784 Views: 6,485 |
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Hi, ❝ How could I validate them? To evaluate the stability of analyte(s) in whole blood, spike minimum of six replicates of LQC and HQC concentrations in the screened whole blood and keep these Stability samples at room temperature (or as specified in the protocol) for a period of minimum 6.0hr. Separate the plasma from spiked whole blood of respective concentration (LQC and HQC). Process and analyze these samples along with separated plasma from freshly spiked six replicates of low & high quality control samples (comparison samples) in the screened whole blood. Calculate the percent stability for analyte(s) in the whole blood. Centrifuge time and temperature are variable factors. — Sudeshna |
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Cristina Basu ● 2008-04-22 11:40 (6288 d 04:02 ago) @ sudeshnamandal1 Posting: # 1787 Views: 6,376 |
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Dear Sudeshna, I appreciate your answer. You say: ❝ Centrifuge time and temperature are variable factors. How can affect the speed and time of centrifugation the efficiency of separation? If the analyte is bounded on the plasmatic proteins, is it necessary to prolong the time? Have a nice day! -- Edit: Standard quotes restored. [Helmut] |
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sudeshnamandal1 ☆ India, 2008-04-22 15:55 (6287 d 23:47 ago) @ Cristina Basu Posting: # 1789 Views: 6,438 |
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Hello Christina, Generally parameters set for centrifuge is 3000 to 4000 rpm at 2-6°C for 10 mins. Cooling conditions are maintained for Protein Precipitation samples. During centrifugation, temperature get increased enough to coagulate the blood. You cannot assume centrifugation will move drug from whole blood to the plasma. Plasma to blood ratio is neccessary to monitor. Experts comments are welcome. — Sudeshna |
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Helmut ★★★   Vienna, Austria, 2008-04-22 16:41 (6287 d 23:02 ago) @ sudeshnamandal1 Posting: # 1790 Views: 6,497 |
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Dear Sudeshna! ❝ Generally parameters set for centrifuge is 3000 to 4000 rpm ... Since the separation effect is dependent on the force applied – not on “revolutions per minute” – such a description is meaningless unless the diameter of the centrifuge’s rotor is stated as well. See this post and the linked document. We routinely applied 2040×g at +4 ℃ for 20 minutes. — Dif-tor heh smusma 🖖🏼 Довге життя Україна! ![[image]](https://static.bebac.at/pics/Blue_and_yellow_ribbon_UA.png) Helmut Schütz ![[image]](https://static.bebac.at/img/CC by.png) The quality of responses received is directly proportional to the quality of the question asked. 🚮 Science Quotes |
Ing. Helmut Schütz