هال

1. SAMPLES
and
BIOMOLECULES
Medical Biochemistry and Molecular
biology department

2. SAMPLE
COLLECTION,
HANDLING AND
STORAGE

3. Sample Collection, labeling, processing,
storage, and transportation, may affect the
results of the tests.

4. Informatio
n obtained
from the
patient and
linked to
Sample
• Time and date of collection.
• Recent diet and supplement use.
• Reproductive information
(menstrual cycle).
• Recent smoking.
• current medication use.
• Recent medical illness.
• Storage conditions.

5. Examples of Bio-
specimens
1. blood
2. urine
3. stool
4. Broncho -alveolar
lavage
5. Exhaled air
6. Hair
7. Nail clipping

6. SPECIMEN HANDLING
1.Verify patient
identity.
2. Verify that
patient is
fasting
if necessary
3. Patient comfortably lying on
bed or comfortably seated for
20 min before specimen
collection.
4. Don’t apply
the tourniquet
for more than
1
min.
5. Patient arm
is
extended.
6.
Determine
the needed
amount of
blood to be
drawn.
7. Draw adequate
amount of blood with
the suitable tube to
yield the necessary
plasma or serum
volume.
8. Gently mix the blood collection tube
with the anticoagulant by inverting it
from 8 to 10 times immediately after
collection.
9. Centrifuge
the sample
within 20-
30 minutes
of
collection.

7. Vacutainers used
in blood sample
collection

8. ADDITIVES IN
DIFFERENT
VACUTAINERS
AND THEIR
ACTIONS.
1. Red
 Additive: None or contains silica particles which act as clot activators.
 What additive does: Clot activator promotes blood clotting with glass or silica
particles.
 Laboratory Uses: Serum testing (glucose, cholesterol, triglycerides, HDL,
potassium, amylase, alkaline phosphatase, BUN, CK, liver enzymes), blood bank,
serology
2. Yellow
 Additive: anticoagulant SPS (Sodium Polyanetholsulfonate) & ACD (acid citrate
dextrose)
 What additive does: Prevents the blood from clotting and stabilizes bacterial
growth.
 Laboratory Uses: Blood and bodily fluid cultures
3. Light Blue
The blue bottle is used for haematology tests
 Additive: Sodium Citrate
 What additive does: Binds and remove calcium to prevent blood from clotting
 Laboratory uses:
PT Prothrombin Time
PTT Partial Thromboplastin

9. ADDITIVES IN
DIFFERENT
VACUTAINERS
AND THEIR
ACTIONS
(CONT.’)
4. Green
5. Lavender
 Additive: EDTA (Ethylenediaminetetraacetic Acid)
 What additive does: Removes calcium preventing clotting of blood
 Laboratory uses: Hematology testing (ESR, CBC, HgBA1c)
6. Grey
 Additive: Potassium oxalate and Sodium fluoride
 What additive does: Sodium fluoride acts as an
antiglycolytic agent to ensure that no further glucose
breakdown occurs within the sample after it is taken.
Potassium oxalate removes calcium and acts as an
anticoagulant.
 Laboratory uses: Chemistry testing, especially
glucose(sugar) and lactate, Glucose tolerance test (GTT)

10. ADDITIVES IN
DIFFERENT
VACUTAINERS
AND THEIR
ACTIONS (CONT.’)
7. Royal Blue
• Additive: Sodium Heparin also Sodium
EDTA.
• Additive prevents thrombin formation.
• Laboratory uses: Chemistry (trace elements
such as Zinc, Copper, Lead and Mercury),
toxicology and nutritional chemistry testing.
8. Black
• Additive: Sodium Citrate.
• Additive forms calcium salts to remove
calcium.
• Laboratory uses: Pediatric ESR.

11. PLASMA
VERSUS SERUM

12. CONTENTS
OF TUBES
SEPARATING
PLASMA

13. BRONCHOALVEOLAR
LAVAGE (BAL)
BAL is used to assess
some occupational
diseases (asbestosis)
Induced sputum sample
and BALF can also provide
sufficient DNA for PCR
assays.

14. EXHALED AIR To evaluate exposure to different substances,
particularly solvents such as benzene and alcohol
To be used as a source of exposure and
susceptibility markers in some diseases as urea
breath test.
Breath urea test (presence of urease positive
organisms such as H. pylori).

15. HAIR Easily available biological tissue.
Provides permanent record of trace elements associated
with normal and abnormal metabolism.
A source for occupational and environmental exposure
to toxic metals.
Good marker for environment tobacco smoke
(ETS) exposure in children.
Hair analysis provides long-term information from
months to years, concerning both the severity and
pattern of drug use.

16. NAIL CLIPPINGS
Toenail or fingernail clippings are obtained in a very easy and comfortable way.
They do not require processing, storage and shipping condition and thus suitable for
large epidemiological studies.
Gives information about levels of trace elements, selenium and arsenic.
Less likely to be contaminated by environmental factors.

17. SALIVA
It is an efficient, painless and relatively inexpensive source of biological materials for
certain
assays.

18. FEACES  Certain cells of interest
Infectious markers (Hepatitis A antigen and H.
Pylori
antigen).

19. SEMEN Evaluate the effects of exposures on endocrine and
reproductive factors.
 Sexual abstinence for at least 2 days but not
exceeding 7 days.
 Should reach the lab within one hour.

20. TEMPERATURE
Specimen collection requires storage system that capable of maintaining the
optimal
temperature for the diverse type of specimens:
-20 degree C, certain items stable, I.e., urine
-70 degree C, DNA, Serum, Hormone, vitamins
-80 degree ,for years

21. SHIPPING
 Sample shipping requirements depends on the time, distance, climate, season,
method of transport, applicable regulations, type of specimen and markers to be
assayed.
 boxes containing dye ice are used to ship and transport samples that require low
temperature. For samples require very low temperature, liquid nitrogen container can be
used
The quantity of dry ice should be carefully calculated, based on estimated time of trip.

22. BIOLOGICAL
MO
LEC
ULES
& ENZYMES

23. BIOMOLECULES
All our biomolecules are
classified into four
groups:
1. Carbohydrates
2. Lipids
3. Proteins
4. Nucleic Acids

24. BIOLOGICAL MOLECULES
TESTING
(a) Benedict`s test for reducing sugar, the iodine test for starch, and the biuret test for
proteins.
(b) The test for catalase enzymes

25. CARBOHYDRATES
Indicators are chemicals that detect the presence of a certain compound.
Benedict’s solution reacts with MOST saccharides that contain a reducing end ( a free
‫ــــ‬OH group).
Sucrose is a notable exception (as it is a non-reducing sugar).
 If a detectable carbohydrate is present, then the indicator changes color, based on how
many carbs are present.

26. ACTIVITY 1:BENEDICT’S
TEST: REDUCING SUGARS
Left to right:
• Benedict's reagent
• Degrees of reducing sugars
RESULTS:
Aqua-blue = negative.
Green to Yellow to orange =
positive.

27. ACTIVITY 2: TESTING FOR
STARCH IKI (IODINE IN
POTASSIUM IODIDE)
 Iodine is used to detect starch.
 Left to right:
IKI only,
starch
solution,
starch solution + IKI.
RESULTS: Yellow-orange =
negative.
• Purple-black = positive.

28. PROTEIN
 Proteins are polymers of amino acids connected by a type of chemical bonds called
“peptide
bond”.
 Biuret reagent can detect proteins contain ≥3 amino acids.

29. ACTIVITY 3: TESTING
FOR POLYPEPTIDES
(PROTEINS) BIURET’S
REAGENT
RESULTS:
Denim-blue =
negative.
Violet color =
positive.
Left to right:
• Biuret's reagent (BrR),
• water + BrR,
• Protein( egg albumin)
• Protein (egg albumin
+ BrR).

30. ACTIVITY 4: DETECTION OF ENZYMES (
CATALASE)
2H2O2 O2+2H2O
Procedure:
• Place few drops of 3% hydrogen peroxide (H2O2) into the tube containing the
enzyme.
• Observe for the evolution of oxygen bubbles.
catalas
e
Left= evolution of oxygen
Right= without evolution of gas

32. THANKS