Is a red top tube referred to as a serum separator tube?

Answer 1

Depends who you buy your red top tubes from, but mostly no.

A serum seperator tube (SST) is usually yellow or gold top, it has a lump of clear gel in the bottom. When spun this gel ends up between the serum and red blood cellsmaking it easier to seperate the serum.

A red top is generally a tube with nothing at all in it. So when spun you end up with serum and clotted red cells but nothing seperating them.

Most other colour tubes contain an anti coagulant preventing the blood from clotting so when spun you end up with plasma and red cells.

The important thing for most tests is the difference between serum and plasma, so a red top and an SST can generally be used for the same tests although SST is often prefered as its easier to work with.