Duke University chemists have demonstrated a laser-based system that can capture three-dimensional images of the chemical and structural changes taking place beneath the surface of human skin.
They say that their work is the first step towards non-surgical screening for malignant skin cancers.
"The standard way physicians do a diagnosis now is to cut out a mole and look at a slice of it with a microscope," said Warren Warren, the James B. Duke Professor of chemistry, radiology and biomedical engineering, and director of Duke's new Center for Molecular and Biomedical Imaging.
"What we're trying to do is find cancer signals they can get to without having to cut out the mole. This is the first approach that can target molecules like hemoglobin and melanin and get microscopic resolution images the equivalent of what a doctor would see if he or she were able to slice down to that particular point," said the researcher.
The distributions of hemoglobin, a component of red blood cells, and melanin, a skin pigment, serve as early warning signs for skin cancer growth. But because skin scatters light strongly, simple microscopes cannot be used to locate those molecules except right at the surface.
Warren says that the new technology developed by him and his colleagues is capable of coaxing both hemoglobin and melanin inside questionable skin moles to emit light by exciting them with highly controlled laser pulses.