Iowa State University researchers find breakthrough method to fight crime
An Iowa State University group has made a scientific breakthrough after finding a new way to use fingerprints to fight crime.
The group has discovered how to measure the age of fingerprints and when a person was at the scene of the crime.
ISU chemistry graduate Paige Hinners is helping to invent the breakthrough. For years, she studied how to measure how long a fingerprint had been deposited in a certain spot. Now, with the help of ISU chemistry professor Young-Jin Lee, they know the answer.
"We were definitely shocked," Hinners said.
"We can tell how old is the fingerprint within a few days," Lee said.
Lee and Hinners discovered a way to measure chemical compounds in fingerprints. They feed the print into a mass spectrometer, and they break it apart with a laser beam.
"Typically about a quarter of the fingerprint is the size we analyze," Hinners said.
The spectrometer can detect microscopic levels of triglycerides, or fat left in a fingerprint. Fresh prints have more fat. The fat begins to fade as the prents get older. A formula allows investigators to determine how old a fingerprint is by measuring the mass or intensity of that fat.
"You can say, not only was it this person, this person was at the crime scene during this time, or this person was present during this time," Hinner said.
It has taken ISU three years to come up with the fingerprint development, and it may take another two years before it can be used in a criminal trial.