Researchers developed a new lipstick analysis method that can help investigators generate leads faster and track down criminals. This new technique can effectively lift lipstick residues from various surfaces and use gas chromatography to analyze the samples.
In recent years, forensic scientists tested many techniques to effectively lift lipstick samples from crime scenes. Unlike what is seen on TV shows or movies, investigators can't just send an evidence to a lab, and in just a matter of days get results that will help track down the bad guys or identify the victim.
In real life, collecting samples and analyzing its chemical makeup takes longer, and they don't come cheap. Current techniques involve the painstaking removal of the lipstick residue and examining them using X-ray diffraction or Raman spectroscopy.
Both require not just specialized equipment, but also distinctive training. Unlike in TV shows, many under-funded forensic laboratories are in short-supply of these two.
A research team from Western Illinois University developed a better way to extract the lipstick residue. Led by researcher Bethany Esterlen, the two-step method involved adding an organic solvent to remove the majority of the lipstick's wax and oil content first. Second, they lift the remaining residue by adding a basic organic solvent.
"Right now we are just lifting samples off of paper, but in the future we are hoping to use different articles and media that could be found at a crime scene," said Brian Bellott, Ph.D., whose lab was utilized in the research.
Chromatography is the process of separating a mixture by allowing it to pass through a solution or a suspension. In gas chromatography (GC), the mixture passes through a vapor. The team also tested thin layer chromatography (TLC) and high performance liquid chromatography (HPLC) in the study.
They found that GC works best. Each lipstick brand has a unique organic molecule structure that provides different chromatography signals.
The team compiled a library of known lipstick brands. Using the lifting technique and chemical analysis method, the researchers can identify the brand of lipstick used. In potential real life setting, the identity of the lipstick brand can help investigators track down a suspect.
The research was presented at the 251st National Meeting & Exposition of the American Chemical Society on Sunday.
Photo: Curt Smith | Flickr
