Silkworms can produce edible, fluorescent silk cocoons (left side of left image); the proteins from the cocoons can be used in codes (right) to verify the authenticity of medications. Credit: Adapted from ACS Central Science 2022, DOI: 10.1021/acscentsci.1c01233
Recent changes, such as the development of online pharmacies and supply chain issues, have made it simpler for counterfeiters to profit from fake or adulterated drugs. Researchers have now constructed edible tags made of fluorescent silk proteins that may be put directly on tablets or in a liquid therapy, according to a study published in ACS Central Science. A smartphone app can scan the codes on the tags to verify the source and purity of the medications.
Of late, the number of online pharmacies has exploded, offering a wide range of pharmaceuticals straight to clients’ homes. Some of these companies are legitimate, while others operate unlawfully, offering poor, wrongly labeled, or tainted with undesired ingredients counterfeit pharmaceuticals.
Furthermore, global supply chain issues have made it simple for counterfeit drugs to enter the market. Pharma businesses use bar codes, QR codes, holograms, and radiofrequency identifiers on the exterior packaging of their goods to build customer confidence. This allows distributors and merchants to control items along the supply chain.
Consumers can’t verify the source of individual pills or liquid dosages inside a container since there aren’t corresponding codes. Fluorescent synthetic materials, such as microfibers and nanoparticles, have been produced as tracking codes by researchers, however, the chemicals are possibly hazardous to consume. Researchers sought to test if silk, which is edible and “generally accepted as safe,” could be put directly on pharmaceuticals and made to glow, assisting consumers in ensuring that their purchases are exactly what they claim to be.
Silkworms were genetically engineered to generate silk fibroins. These are edible proteins that give silk fibers their strength and can be labeled with cyan, green, or red fluorescent proteins. They created luminous polymer solutions by dissolving the fluorescent silk cocoons, which they then put in a seven-by-seven grid over a thin, 9-mm-wide layer of white silk.
An app developed by the researchers can scan the luminous pattern using optical filters over the phone’s camera, decoding the digital key with a deep learning algorithm and opening a webpage with information on the drug’s origins and legitimacy. Because some liquid pharmaceuticals contain alcohol, the researchers put a coded silk film in a transparent bottle of Scotch whiskey and discovered that the app could still detect the luminous code.
Finally, the researchers discovered that gastrointestinal enzymes break down the luminous silk proteins, implying that the silk codes are not only edible but also digestible. According to the researchers, putting these edible code appliqués on tablets or in liquid dosages might help patients and their caregivers avoid inadvertently consuming fake medications.