Scientists have always had to collect blood at the crime scene and transport it back to the lab for testing.
Until now, blood DNA tests could determine someone's ethnicity and sex, but they couldn't determine age. The tests also took several days to yield results. But now things are changing.
A new ACS publications study could help crime scene experts better analyze blood evidence. The study researchers developed a new blood test that can be used at a crime scene to determine someone's age range from blood left at the scene. The test works with blood samples collected within two days of being deposited.
The test measures the levels of an enzyme, called alkaline phosphatase, in blood. The levels of this enzyme change in the body between childhood and adulthood.
Researchers completed the study by synthesizing human blood. They then calculated the ages of the people it could have come from. When trialing the blood test, the team was able to correctly identify ages at an almost 100% success rate.
The blood test is still in early development, which means, of course, that there are a couple of problems that still require further testing. For example, scientists are still unsure about how much human blood they need for the test to be accurate. Also, since many crime scenes are discovered more than 2 days after the blood is deposited there, it may be too diluted to use in tests if the crime scene is too old.