Researchers have developed a method that uses smartphone-derived images to visually identify bacteria on the skin and in the mouth.
Smartphones have become an integral part of people’s daily lives. A new approach developed by researchers could enhance the utility of the devices even more by allowing people to spot potentially harmful bacteria on their skin and in their mouth using their smartphone camera.
The researchers at the University of Washington (UW) have detailed their work in a paper titled ‘Smartphone-enabled snapshot multispectral autofluorescence imaging and its application for bacteria assessments in skin and oral cavity,’ published in the journal Optics and Lasers in Engineering.
“Bacteria on skin and in our mouths can have wide impacts on our health — from causing tooth to decay to slowing down wound healing,” Ruikang Wang, Professor of Bioengineering and Ophthalmology at UW, said in a release. “Since smartphones are so widely used, we wanted to develop a cost-effective, easy tool that people could use to learn about bacteria on skin and in the oral cavity.”
The team designed their approach to show porphyrin, a by-product of bacterial growth and metabolism, using smartphone-derived images in combination with image-processing methods. To enhance the smartphone camera, they attached a 3D-printed ring containing 10 LED black lights, around a smartphone case’s camera opening.
While the LED lights ‘excite’ porphyrins, causing them to emit a red fluorescent signal that the smartphone camera can pick up, proteins or oily molecules produced by human bodies, as well as skin, teeth and gums, will not glow red under LED, Qinghua He, lead author of the paper explained.
Using this method, the team was able to generate a “pseudo-multispectral” image consisting of 15 different sections of the visible light spectrum, rather than the three in the original RGB (red, green, and blue) smartphone-derived image, UW noted.
The pseudo-multispectral images make it possible to clearly see porphyrin clusters on the skin and in the mouth.
“Generally, the more porphyrins you see on skin surface, for example, the greater difficulty you see with wound-healing and acne,” Yuandong Li, co-author of the paper, said.
The team’s approach can be tweaked to spot other bacterial signatures that also shine under LED, to help identify potentially problematic bacteria in other medical contexts, UW noted.
“Our bodies are complex environments, and this approach has great potential to look at many types of problems,” Wang said.