Raman effect to detect phoney art, chemical weapons

An international research team has developed nanotechnology that harnesses surface-enhanced Raman spectroscopy (SERS) to detect trace amounts of molecules in fraudulent paintings, diseases, chemical weapons and more.

Led by University at Buffalo (UB) engineers, the new method makes SERS simple and more affordable.

"The technology we're developing - a universal substrate for SERS - is a unique and, potentially, revolutionary feature," said lead author Qiaoqiang Gan from UB.

"It allows us to rapidly identify and measure chemical and biological molecules using a broadband nanostructure that traps wide range of light," Gan added.

The universal substrate can trap a wide range of wavelengths and squeeze them into very small gaps to create a strongly enhanced light field.

"It acts similar to a skeleton key. Instead of needing all these different substrates to measure Raman signals excited by different wavelengths, you'll eventually need just one. Just like a skeleton key that opens many doors," co-author Nan Zhang said.

Traditional substrates, or the silicon surfaces on which liquid samples are deposited, are typically designed for only a very narrow range of wavelengths.

This is problematic because different substrates are needed if scientists want to use a different laser to test the same molecules.

In turn, this requires more chemical molecules and substrates, increasing costs and time to perform the test. The new technology has a wide range of applications.

"The ability to detect even smaller amounts of chemical and biological molecules could be helpful with biosensors that are used to detect cancer, malaria, HIV and other illnesses," the researchers said.

"This could be helpful detecting forged pieces of art as well as restoring ageing pieces of art," Gan said.

"Also, the technology could improve scientists' ability to detect trace amounts of toxins in the air, water or other spaces that are causes for health concerns. And it could aid in the detection of chemical weapons," he added.

The study was published in the journal Advanced Materials Interfaces.