id characterization of blood bloodstain
Skip this Video
Download Presentation
ID & Characterization of Blood & Bloodstain

Loading in 2 Seconds...

play fullscreen
1 / 40

ID & Characterization of Blood & Bloodstain - PowerPoint PPT Presentation

  • Uploaded on

ID & Characterization of Blood & Bloodstain. BEFORE DNA THERE WAS:. SEROLOGY. Serology. examination & analysis of body fluids. Serology. STAINS often deteriorated and degraded. Serology. Correct steps must always be followed - PROTOCOL. Blood Facts.

I am the owner, or an agent authorized to act on behalf of the owner, of the copyrighted work described.
Download Presentation

PowerPoint Slideshow about 'ID & Characterization of Blood & Bloodstain' - zared

An Image/Link below is provided (as is) to download presentation

Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author.While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server.

- - - - - - - - - - - - - - - - - - - - - - - - - - E N D - - - - - - - - - - - - - - - - - - - - - - - - - -
Presentation Transcript
  • examination & analysis of body fluids


  • often deteriorated and degraded
  • Correct steps must always be followed - PROTOCOL
blood facts
Blood Facts

The average adult has about FIVE liters of blood inside of their body, which makes up 7-8% of their body weight.

Blood is living tissue that carries oxygen and nutrients to all parts of the body, and carries carbon dioxide and other waste products back to the lungs, kidneys and liver for disposal. It also fights against infection and helps heal wounds, so we can stay healthy.

There are about one billion red blood cells in two to three drops of blood. For every 600 red blood cells, there are about 40 platelets and one white cell.

presumptive testing
Presumptive testing

Negative result

  • questioned stain is not likely blood

Positive result

  • questioned stain is likely blood
presumptive screening tests
Presumptive Screening Tests
  • Presumptive tests produce a color reaction or release of light
  • Tests rely on hemoglobin presence
catalytic color test
Catalytic Color Test
  • Sample a stain with a clean, moist cotton swab
  • Add a drop of reagent
  • Add a drop of hydrogen peroxide
  • Color will develop immediately
catalytic color test1
Catalytic Color Test


  • Benzidine Alder – blue-dark blue
  • Phenolphtalein-Kastle-Mayer Test – pink
  • O-Tolidine test – blue
  • Leucomalchite Green (LNG) – green
  • Tetramethylbenzidine- Hemastix – green –blue green
  • light is emitted as a product of the chemical reaction
  • light is emitted when a substance is exposed to a shorter wavelength of light
chemiluminescence fluorescence
Chemiluminescence & Fluorescence
  • More sensitive than color tests
  • May damage blood stain (no blood/DNA typing)

Used to locate and define areas of blood

    • old blood stains
    • cleaned floor
  • Method similar to color test
  • combined with oxidant and sprayed over area thought to contain blood
  • Emits a blue-white to yellow green glow
  • Extremely sensitive – 8 paint layers
  • combined with oxidant and sprayed over area thought to contain blood
  • Fluoresces when treated with a UV light
  • includes a thickener
  • makes it more effective on vertical surfaces
  • Study showed no interference with DNA analysis
confirmatory test for blood
Confirmatory test for Blood
  • Confirms presence of blood
  • Several test use crystal formation to detect hemoglobin

2 types of tests

  • Teichmann test
  • Takayama test
species origin
  • Most methods test for serum proteins
  • Serum proteins are found in all animals, but are slightly different
  • Species ID methods based on antigen/antibody interactions
microscopic views
Fish Blood

Bird Blood

Horse Blood

Cat Blood

Frog Blood

Human Blood

Snake Blood

Dog Blood

genetic markers in blood

If a stain is blood, and it is human blood, then whose is it?

  • Blood Group Markers
  • Protein/Enzyme Markers
  • DNA
blood group markers
Blood Group Markers
  • ABO Markers
  • Lewis System
  • Rhesus System

Many blood group markers, including:

genetic markers in blood1
Genetic Markers in Blood
  • Your blood group is genetically controlled and a lifelong characteristic

Types of markers

    • Antigen Marker
    • Protein Marker
    • Enzyme Marker
blood group markers1


  • Look at antigens on Red Blood Cells
  • antigens are glycoproteins
  • are attached to outside of cell
introduction to blood
Introduction to Blood

ABO blood groups found on outside of cell

blood group markers2
Blood Group Markers

ABO Markers (antigen and antibodies)

  • person will have antibodies (A or B) to whatever blood group he/she doesn’t have
  • Otherwise, a persons blood would clump up and cause death
blood group markers3
Blood Group Markers

ABO Markers (antigen and antibodies)

blood group markers4
Blood Group Markers

ABO Markers (antigen and antibodies)

blood group markers5
Blood Group Markers

ABO Markers (antigen and antibodies)

blood group markers6
Blood Group Markers

ABO Markers (antigen and antibodies)

blood group markers7
Blood Group Markers

ABO Markers (antigen and antibodies)

blood group markers8


  • Testing is similar to species test
  • An anti-A, anti-B, or anti-AB antiserum (containing antibodies) is reacted with blood stain to detect blood cells
  • A, B, or AB blood cells are reacted with blood stain to detect antibodies
blood group markers9


  • Tests can get complicated with absorbing and releasing cells
  • Final step is usually testing for agglutination (blood clumping)
blood group markers10


  • A cells clump with anti-A
  • B cells clump with anti-B
  • AB cells clump with both
  • O cells do not clump
rh factors
Rh Factors
  • Scientists sometimes study Rhesusmonkeys to learn more about the human anatomy because there are certain similarities between the two species. While studying Rhesus monkeys, a certain blood protein was discovered. This protein is also present in the blood of some people. Other people, however, do not have the protein.
  • The presence of the protein, or lack of it, is referred to as the Rh (for Rhesus) factor.
  • If your blood does contain the protein, your blood is said to be Rh positive (Rh+). If your blood does not contain the protein, your blood is said to be Rh negative (Rh-).

A+ A-B+ B-AB+ AB-O+ O-





Blood Transfusions

A blood transfusion is a procedure in which blood is given to a patient through an intravenous (IV) line in one of the blood vessels. Blood transfusions are done to replace blood lost during surgery or a serious injury. A transfusion also may be done if a person’s body can't make blood properly because of an illness.

Who can give you blood?

People with TYPE O blood are called Universal Donors, because they can give blood to any blood type.

People with TYPE AB blood are called Universal Recipients, because they can receive any blood type.

Rh +  Can receive + or -

Rh -  Can only receive -

Universal Donor

Universal Recipient