How to Centrifuge Blood Samples: A Quick Guide

01.What you're separating

Blood centrifugation splits whole blood into three layers by density. Getting clean layers is the whole point.

• Top — plasma or serum (pale yellow, lowest density)
• Middle — buffy coat (white blood cells + platelets)
• Bottom — red blood cells (~40–45% of volume)

Remember: separate serum (clot first) from plasma (anticoagulant tube) — choosing the wrong collection tube fails the test from the start.

02.Four steps to a clean run

Most errors come from skipped balancing, wrong RCF, or ignoring temperature — all preventable with a written SOP.

03.Key parameters at a glance

Assay	RCF (g)	Time
Serum biochemistry (gold SST)	1000–2000	10 min
Plasma (emergency)	1500–3000	10 min
PRP preparation	~300–600 (1st)	6–10 min
Nucleic acid / cell pellet	3000–12000	5–15 min

RCF vs RPM: the same RPM gives more force with a larger rotor radius. Always set and compare by RCF — it reflects the real separation power.

04.Choosing a centrifuge

• Capacity & rotor: match your tube sizes (1.5/15/50 ml, 96-well) and per-run volume.
• Refrigeration: choose a refrigerated model for coagulation, nucleic acid, or biobank work.
• Max RCF: judge separation power by g, not just RPM.
• Safety: imbalance detection, overspeed protection, and CE / IEC 61010 compliance.