Fake seeds can cost farmers more than two-thirds of their expected yield and threaten food security. A traceable silk label can help.
Average yields in Africa have always been far below expectations, and one important reason is the prevalence of fake seeds, which germinate much less frequently than genuine seeds. The World Bank estimates that half of the seeds sold in some African countries are fake.
Many attempts have been made to prevent this counterfeiting by tracking labels, but none have proven effective. Among other things, such labels were vulnerable to hacking due to the deterministic nature of the encoding system. But now, a team of researchers at MIT has come up with a kind of tiny biodegradable tag that can be applied directly to the seeds themselves, providing a unique, randomly-created code that cannot be replicated.
The new system, which uses tiny dots of silk-based material, each containing a unique combination of different chemical characteristics, was described in a paper by MIT engineering dean Anantha Chandrakasan, Benedetto professor of civil and environmental engineering, in the sciences. Marelli, postdoc Hui Sun, and graduate student Saurav Maji.
Counterfeiting is a huge global problem, affecting everything from drugs to luxury goods, researchers say, and various systems have been developed to deal with it. rice field. However, despite the potentially severe consequences, the problem has received less attention in the agricultural sector. For example, in sub-Saharan Africa, the World Bank estimates that counterfeit seeds are, on average, less than one-fifth as likely as maize and less than one-third as likely as rice. is.
Marelli explains that the key to the new system is to create randomly generated physical objects whose exact configuration is virtually impossible to replicate. The labels they create “leverage randomness and uncertainty in the process of application to generate a unique signature feature that is readable and cannot be duplicated,” he says.
What they’re dealing with is basically the very old job of keeping things from being stolen. And you can try everything you can, but in the end, nothing is really unbreakable because someone is smart enough to figure out how to do it all the time. doing is almost impossible, if not impossible, or requires so much effort that it is no longer worthwhile. ”
The idea of ”uncloning” code was originally developed as a way to protect the reliability of computer chips, explains Chandrakasan, a professor of electrical engineering and computer science at Vannevar Bush. “In an integrated circuit, individual transistors have slightly different characteristics and are built with device variations,” he explains. Once you have this, you can use that unique ID as part of your security protocol. Things like transistor variability are hard to replicate from device to device, resulting in uniqueness rather than storing a specific fixed ID. This concept is based on what is known as a physically irreproducible feature (PUF).
The team decided to apply PUF principles to the fake seed problem. The use of silk protein was a natural choice because this material is not only harmless to the environment, but is also classified as “commonly” by the Food and Drug Administration. No special approval is required for use.
“You can also coat it on the seeds,” Maji says. So the idea is that every seed or every bag can have its own signature. ”
While developing effective secure system solutions has long been one of Chandrakasan’s areas of expertise, Marelli has spent years developing systems to apply silk coatings to a wide variety of fruits, vegetables and seeds. A system for enhanced security.
“The challenge was what form factor to give the silk so that it could be manufactured very easily,” says Sun. They developed a simple drop-casting approach that produced tugs less than a tenth of an inch in diameter. The second challenge was to develop “a way to read the uniqueness in a very high-throughput and easy way.”
Regarding the unique silk-based code, Marelli said: The resulting unique patterns can be read not only by spectroscopes and handheld microscopes, but also by regular mobile phone cameras equipped with macro lenses. Processing this image locally he can generate a PUF code and send it to the cloud for comparison against a secure database to verify the authenticity of the product. “It’s random, so you can’t replicate it easily,” he says Sun. “One cannot predict it without measuring it.”
Also, the number of possible permutations resulting from the method of mixing the four basic types of colored silk nanoparticles is astronomical. “We were able to show that 128 bits of random security can be generated with a minimal amount of silk,” he says. “So this gives rise to 2 to the 128th possible combination, which is very difficult to crack given the computational power of state-of-the-art computing systems.”
“For us, this is a good testbed for thinking outside the box and how we can take a more democratic path,” Marelli said. In this case, it means “something that can be literally read on a mobile phone, manufactured without advanced manufacturing techniques, without entering a clean room, by simply drop-casting a solution.”
Additional work will be required to make this a viable commercial product, Chandrakasan says. “It will require the development of large-scale reading” via smartphones. “So it’s clearly a future opportunity.” It shows a clear path to the day when it can be verified.
Original: Tackle Counterfeit Seeds with ‘Uncloneable’ Labels
Than: Massachusetts Institute of Technology
