Final answer:
Serum separator tubes use silicon dioxide (SiO₂), a type of glass formed from silicon and oxygen, to separate the serum from other blood components after centrifugation.
Step-by-step explanation:
The glass particles present in a serum separator tube are composed of silicon dioxide (SiO₂). Serum separator tubes often contain a gel that forms a barrier between the serum and blood cells after centrifugation. Silicon dioxide is a common type of glass and is also found in sand. This material is used in these tubes because of its physical properties that help to facilitate the separation process of the serum from other blood components after centrifugation. It's important for the medical procedures that require serum for various diagnostic tests.