The low-cost, portable, paper-based sensor can also be used for food and beverage applications, and could even be used to help identify new medicinal plants in a remote jungle, the researchers claim.
The research was presented as a paper during the 254th Nation Meeting and Exposition of the America Chemical Society earlier this week and there is also a video to illustrate the technology that can be viewed by clicking here.
A versatile labelling technology
Although the potential applications for the technology are far-reaching, the researchers believe that cosmetics and personal care products could benefit because spoilage not only compromise the efficacy of products, but can lead to potentially dangerous bacterial contamination.
"I've always been interested in developing technologies that are accessible to both industry and the general population," Silvana Andreescu, Ph.D., said.
"My lab has built a versatile sensing platform that incorporates all the needed reagents for detection in a piece of paper. At the same time, it is adaptable to different targets, including food contaminants, antioxidants and free radicals that indicate spoilage."
The sensor technology has been developed around nanostructures that are used to catch and bind to compounds, such as the bacteria that causes spoiling in products.
"Most people working on similar sensors use solutions that migrate on channels," Andreescu said.
"We use stable, inorganic particles that are redox active. When they interact with the substances we want to detect, they change color, and the intensity of the change tells us how concentrated the analyte is."
In search of antioxidants
Andreescu said that the initial research work focused on detecting antioxidants in tea and coffee, and that because of its portability, the technology could also be used in the remote regions, such as the jungle.
Latterly, the focus of the research turned to other applications, specifically ochratoxin A, a fungal toxin commonly found in a range of products, including cereals and coffee.
This ultimately led to the development of the paper-based devices that change colour once bacterial contamination occurs in a range of cosmetic, personal care and food products.