Smartphone Spectrometer

A new lab-on-a-chip that’s small enough to fit inside a smartphone could change the way consumers shop for food. Known as Hertzstück, the prototype sensor is actually a miniature spectrometer that can identify the chemical make-up of a wide variety of materials, including food, textiles, and other consumer products.

Four tiny incandescent lamps illuminate a sample with low-intensity infrared radiation. Each chemical component of the sample will vibrate at a unique frequency, which can be compared to a database of known infrared signatures to determine its composition. A smartphone app analyzes the signals and displays the results. The device will help farmers by identifying whether the herbicides and pesticides they are using are genuine or substandard counterfeits, and by determining the best time to harvest crops. But an even bigger market could come from testing for “food fraud” and adulteration, a major concern in the food industry today.

The ability to analyze food on the spot will enable consumers to identify products that have been deliberately mislabeled — such as olive oil that has been mixed with sunflower oil, or high fructose corn syrup that is being sold as honey. In these days of escalating food counterfeiting, it may prove to be especially important for avoiding reactions to potentially harmful allergens, such as peanuts, wheat, or dairy. The technology can even be used to analyze the fiber content of clothing — including silk, cotton, and polyester — to make sure that buyers are getting what they’re paying for.