The various tests used for the examination of blood during forensic investigation.

1. GURU GHASIDAS VISHWAVIDHYALA
BILASPUR, C.G.
DEPARTMENT OF FORENSIC SCIENCE
TOPIC:- COMPONENT AND EXAMINATION OF BLOOD
SUBMITTED BY:- SUBMITTED TO:-
PAHELI SHARMA Dr. I. ARJUN RAO
17205257 FORENSIC BIOLOGY
(B.Sc 5th semester) AND SEROLOGY

2. CONTENTS
• INTRODUCTION
• COMPONENTS OF BLOOD
• EXAMINATION OF BLOOD
• PRELIMINARY TESTS OF BLOOD
• CONFIRMATORY TESTS OF BLOOD
• FORENSIC SIGNIFICANCE OF BLOOD
• REFERENCE

3. INTRODUCTION
• Blood is the most well known & significant evidence
in modern criminal justice system.
• It has been always considered as a class evidence in
criminal justice system.
• As every contact leaves a trace(Locard’s Exchange
principle)- given by Dr. Edmond Locard leaves the
clue for forensic investigation.

4. COMPONENTS OF BLOOD
Blood constitutes 8% of the human body weight . It is
made up of fluid portion plasma( which constitute of
55% of total blood) cellular parts,proteins, enzymes
and inorganic substances.

5. ERYTHROCYTES/RBC- It contains red pigment called as Hb which is
made up of Ferro-Protoporphyrin. These cells do not contain nucleus &
donot contain genetic material. It helps in transportation of oxygen.
LEUCOCYTES/WBC- It contains nucleus.It is subjected to most intense
examination by forensic scientists because it helps in DNA analysis
(individualization).It helps in defence mechanism. It is of 2 types:
Granulocytes(Neutrophils ,Eosinophils ,Basophils) and Agranulocytes
(Lymphocytes ,Monocytes).
THROMBOCYTES/PLATELETS- These are without nucleus and helps in
blood clotting.

6. EXAMINATION OF BLOOD
• PRELIMINARY TEST-
1. Kastlemeyer Test/Phenopthaline Test
2. Leuco Malachite Green (LMG) Test
3. Tetra methyl Benzidine (TMB) Test
4. Luminol Test
5. Fluorescin Test
• CONFIRMATORY TEST-
1. Takayama Test (Haemochromagen crystal assay)
2. Tiechmann’s Test (Hematin crystal assay )

7. PRELIMINARY TESTS
PRINCIPLE- These test is based on oxidation reduction reaction . Heme is utilized as a
catalysts and hydrogen peroxide is utilized as an oxidising agent.In the
presence of heme the colourless substrate is oxidized yielding a product with
colour chemilumensence and fluorescence.
KASTLEMEYER/PHENOPTHALINE TEST- ( Phenopthaline, KOH ,Zn dust ,distilled
water ,EtOH ,Hydrogen peroxide)
Result- An intense pink colour indicates of hthe presence eme content.
TMB TEST- Sodium acetate, ,glacial acetic acid, TMB reagent distilled water H2O2
Result –An immediate blue green colour indicates the presence of heme content.

8. LMG TEST – LMG reagent glacial acetic acid distilled water Zn dust 3% hydrogen
peroxide.
Result- An intense green colour shows the presence of heme content.

9. LUMINOL TEST- Sodium carbonate luminol powder distilled water hydrogen
peroxide .(Best to identify latent bloodstains and footprints & fingerprints)
Result- An immediate blue colour chemiluminescence shows the activity of heme
content.
FLUORESCEIN TEST- NaOH fluorescein hydrogen peroxide distilled water.
Result- An immediate green colour fluorescence shows the presence of heme
activity (important for latent prints and blood development).

10. CONFIRMATORY TESTS
TAKAYAMA TEST- Standard glucose solution NaOH pyridine distilled water.
Result- The appearance of pink needle shaped crystals of pyridine Ferro
protoporphyrin is a positive reaction for heme & confirms the presence of blood.
TIECHMANN’S TEST- KCl glacial acetic acid distilled water.
Result- the appearance of brown rhombohedral crystals of ferro protoporphyrin
chloride is a positive reaction for heme & confirms the presence of blood.(better for
aged samples).

11. FORENSIC SIGNIFICANCE OF
BLOOD
• It links a victim to a suspect via locard exchange principle.
• Blood stain pattern reveals about position and movement during crime.
• It destroys self defence arguments of suspect.
• Individualization of blood can be done blood typing and DNA profiling.
• Alcohol and drug content can be determined from wet blood.
• Freshness of blood can be detected by serum(it clots few minutes after
exposure to air).
• DNA analysis has allowed forensic scientists to associate blood to single
individual.
• Sex can be determined by identification of baar bodies(if present sex is female).
• BLOOD ANALYSIS NEEDS FOLLOWING QUESTIONS TO ANSWER:-
Is the sample,blood?
Is the sample human blood or animal blood?
If the blood is of human origin .How closely it is associated to particular individual?

12. REFERENCE-
1. Richard Li (Forensic biology & serology)
2. www.Slideshare.net
THANK YOU