Research scientists Dr. Jason Guicheteau and Dr. Ashish Tripathi use the Portable Microscopy Chemical Detection System to test samples containing trace amounts of particles and identify the substance. (Gabriella White/U.S. Army)
Troops could one day carry portable devices to detect the “chemical fingerprint” of hazardous substances in the field, thanks to a system developed by Army researchers at Aberdeen Proving Ground, in Maryland.
Weighing about 10 pounds, the PMCDS — short for Portable Microscopy Chemical Detection System — is both a microscope and a spectrometer that can read the presence of amounts of substances smaller than the human eye can detect.
Developed by the U.S. Army Combat Capabilities Development Command Chemical Biological Center (DEVCOM CBC), the device has already been used to identify narcotics such as fentanyl at sites along the U.S.-Mexico border, according to the Army.
Its primary role for now is in drug identification, but follow-on testing could expand its use to combat or the detection of biochemical warfare substances or hazardous materials, the Army said.
The system first locates potential threats using its microscope, then shoots a laser capable of capturing a “Raman spectrum” — the unique characteristics of any given substance. The system then matches the chemistry of the captured sample against an extensive library of known chemicals, irritants and other dangerous materials.
“Current Raman systems are for bulk detection,” said Dr. Jason Guicheteau, an Army chemist on the project. “The challenge is when it becomes invisible or it’s a residue. We went from bulk detection to trace detection.”
Because it uses a microscope and a spectrometer, the system does not need to destroy the sample to analyze it, unlike some traditional identification methods.
“With the PMCDS, we can take an oxycodone pill that looks normal but isn’t,” Guicheteau explained. “Agents can scan it and instantly know it’s fake and potentially laced with fentanyl.”
The device can detect as little as 1% fentanyl.
“We needed to detect particles on various surfaces hours or days after contamination,” said Dr. Ashish Tripathi, DEVCOM CBC physical scientist.
Next-generation plans for the project aim to expand PMCDS into a chemical-biological sensor capable of detecting droplets as well as solids.
