Engineers at the University of California – Los Angeles have created a cell phone attachment that may be able to rapidly and inexpensively detect pathogenic E. coli bacteria in liquefied food samples or water.
The device, which is portable, lightweight and compact and can attach to an existing cell phone camera, acts like a fluorescent microscope. The device was successful in tests using a specially-prepared buffer solution and milk and may be able to detect other pathogens through the use of different antibodies.
To use the device, scientists pump a sample into a series of small tubes in the device that have been treated with E. coli antibodies and lit with battery-powered light-emitting diodes. The light excites the labeled E. coli particles and emissions from quantum dots are imaged using the cell phone camera and an additional lens. The phone then quantifies the florescent light emission from each tube to determine the concentration of E. coli bacteria in the sample.
The details of the study were published in The Royal Society of Chemistry. The researchers were from the UCLA Henry Samueli School of Engineering and Applied Science. Authors of the study include Aydogan Ozcan, an associate professor of electrical engineering and bioengineering, Hongying Zhu, an electrical engineering postdoctoral scholar, and Uzair Sikora, an electrical engineering undergraduate student.