Sample Types

Question 1

List the different types of tubes

Answer 1

Plasma gel orange

Serum brown

Yellow

Serum white

EDTA

Gel free lithium heparin

Metal free lithium heparin

Question 2

Write about plasma gel orange tubes

Answer 2

Most commonly used tube in biochem
Contains gel and lithium heparin anticoagulant
When spun sample is divided into plasma, gel and rbcs
Most tests ran on PL e.g renal, bone etc

Question 3

Write about yellow tubes

Answer 3

Contain sodium fluoride as an anticoagulant

Used for testing glucose

Question 4

Why does glucose testing require a different tube than plasma gel orange?

Answer 4

Glycolysis by the rbcs must be prevented
Lithium heparin in PGO tubes doesn’t prevent glycolysis thusly any glucose measured would be depressed
Yellow tubes contain sodium fluoride which prevents glycolysis and thus allows for accurate measurement of glucose

Question 5

Write about brown tubes

Answer 5

Tubes used for serum samples
(Sodium?) Heparin is the anticoagulant used
Contains gel

Question 6

What tests are carried out in brown serum tubes

Answer 6

LDH
Lithium
Digoxin
Ampikacin

Question 7

Write about white tubes

Answer 7

Serum tubes without gel
Used in mass spec

Question 8

Write about red tubes

Answer 8

EDTA
Used for HbA1c
Used for NT-BNP

Question 9

Write about gel free lithium heparin tubes

Answer 9

These are new
Used for certain coherts of patients e.g. leukaemia
They have proteins which are heavier than the gel
Plasma will not separate out
Will have a layer of gel on top if Normal tube used

Question 10

When might a metal free lithium heparin bottle be used

Answer 10

For measuring copper