A Smartphone Camera that Illuminates Skin Bacteria Causing Acne, Dental Plaques

Representational Picture

University of Washington researchers have developed a method that uses smartphone-derived images to identify potentially harmful bacteria on skin and in oral cavities. The approach, outlined in a paper published in the May issue of Optics and Lasers in Engineering, can visually identify microbes on skin contributing to acne and slow wound healing, as well as bacteria in the oral cavity that can cause gingivitis and dental plaques.

The researchers' approach yielded a relatively low-cost and quick method that could be used at home to assess whether potentially harmful bacteria are present on skin and in the oral cavity.

The researchers combined a smartphone-case modification with image-processing methods to illuminate bacteria on images taken by a conventional smartphone camera.

Modified Smartphone

Ruikang Wang, a UW professor of bioengineering and of ophthalmology and also led the research team, said --

Bacteria on skin and in our mouths can have wide impacts on our health — from causing tooth to decay to slowing down wound healing. 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.

"A" is an RGB autofluorescence image, taken using the LED-modified smartphone, of the right side of the nose bridge of a research volunteer. “B” is a close-up of the section in “A” outlined in red dash marks.He et al., Optics and Lasers in Engineering, 2021

Bacteria emit colors beyond red, green, and blue, and the typical smartphone camera misses those colors. Researchers augmented the smartphone camera capabilities by attaching a 3D-printed ring that contained 10 LED black lights around the smartphone case’s camera opening. The researchers used the LED-augmented smartphone to take images of the oral cavity and skin on the face of two research subjects.