An “invisible code” for products: improving plastic recycling and tackling counterfeiting and greenwashing

Invisible “codes” that can be applied to goods and products to ensure traceability and strengthen plastic recycling systems may soon become a reality. This innovation is being developed within ELISET (Emission Lifetimes technology for sorting, Security and Traceability), a project funded with €2.36 million under the EIC Transition programme, which supports the advancement of innovative solutions from the laboratory to the market.

The project represents a further step in a research and technology transfer pathway that began over ten years ago at the University of Bologna and continued with the creation of the spin-off Sinbiosys.

“ELISET comes at a crucial time for Europe. The plastic recycling sector is facing significant challenges, including economic pressures, increasing demands in terms of quality and quantity, and the need to make recycling truly competitive,” explains Paola Ceroni, Professor at the Department of Chemistry “Giacomo Ciamician” at the University of Bologna and co-founder of Sinbiosys. “In this context, having material streams that are easier to identify and more homogeneous becomes essential. It is a key condition for increasing the value of recycled materials and strengthening the sector’s industrial sustainability.”

The solution developed within ELISET is based on luminescent silicon nanocrystals (silicon quantum dots). These act as invisible markers that do not alter the appearance of products but allow for rapid and reliable identification through dedicated optical systems. Beyond the emission “colour”, the technology also uses the luminescence decay time—a temporal signature that makes the coding more robust and particularly effective for both traceability and anti-counterfeiting purposes.

“This approach makes it possible to embed traceability directly into materials and connect it to digital systems for supply chain management,” adds Ceroni. “With ELISET, we aim to demonstrate that advanced research results can be translated into concrete and timely solutions to address some of the most pressing challenges of the ecological transition—from improving recycling quality to ensuring transparency in value chains, as well as protecting products and materials.”