Aydogan Ozcan, leader of the research team at the University of California, Los Angeles, Henry Samueli School of Engineering and Applied Science, said the iTube attachment uses the cellphone's built-in camera. Along with an accompanying smartphone application, the device runs a test with the same high level of sensitivity a laboratory would.
Several products detect allergens in foods, but require bulky equipment, making them ill-suited for use in public settings. Weighing less than 2 ounces, the attachment analyzes a test tube-based allergen-concentration test known as a colorimetric assay, Ozcan said.
Food samples were initially ground up and mixed in a test tube with hot water and an extraction solvent, and the mixture was allowed to set for several minutes. Then, following a step-by-step procedure, the prepared sample was mixed with a series of other reactive testing liquids, the researchers said.
The sample is measured optically for allergen concentration through the iTube platform, using the cellphone's camera and a smart application running on the phone, Ozcan said.
The kit digitally converts raw images from the cellphone camera into concentration measurements detected in the food samples. The device can quantify how much of an allergen is in a sample, in parts per million.
The iTube platform tests for a variety of allergens, including peanuts, almonds, eggs, gluten and hazelnuts, Ozcan said.