C09 | Argirium SUNc®: an innovative formulation based on silver nanoparticles for sanitisation in the food industry

A. Mancusi¹, Y.T.R. Proroga¹, R. Marrone², O. Di Maro¹, S. Girardi¹, L. Scotti³, T. Cardellicchio¹, M. Egidio². | ¹Istituto Zooprofilattico Sperimentale del Mezzogiorno, Dip. Coordinamento di Sicurezza Alimentare; ²Università Federico II di Napoli – DMVPA Dip. Medicina Veterinaria e Produzioni Animali; ³IIS “Alessandrini-Marino”, Teramo.

Purpose. Microbiological contamination along the food chain is one of the main challenges for food safety. Pathogens such as Listeria monocytogenes, Salmonella spp., Escherichia coli and Pseudomonas aeruginosa, known for their ability to form biofilms and their growing resistance to conventional antimicrobials, require the development of effective and sustainable alternative solutions. In this context, silver nanoparticles (AgNPs) are emerging as promising tools for microbiological control, thanks to their unique antimicrobial properties and low propensity to induce resistance. This project evaluated the effectiveness of the Argirium SUNc^® formulation, based on Silver Ultra Nano Clusters (<2 nm), in sanitising surfaces in industrial food environments. Argirium SUNc^® was synthesised using a patented electrochemical process, using only pure silver and ultrapure water, without the use of stabilisers or additives. The resulting nanoparticles, characterised by sizes smaller than 3 nm and multiple oxidative states (Ag⁺, Ag²⁺, Ag³⁺), exhibit extraordinary stability in solution and a redox potential higher than that of the oxygen/ozone pair. In vitro studies conducted on foodborne pathogens (including S. aureus, E. coli, L. monocytogenes, S. typhimurium, P. aeruginosa) have shown high antimicrobial efficacy even at low concentrations (<1 µg/mL), with results exceeding 99% inhibition for Gram-negative bacteria after only 15-60 minutes of contact. Gram-positive bacteria, which are known to be more resistant due to their cell wall structure, still showed significant inhibition at the tested operating concentrations. Methods. To evaluate its effectiveness on an industrial scale, Argirium SUNc^® was tested in two formulations (spray and bio-gel) at three food companies representing different sectors: meat, dairy and fish. Environmental surfaces, utensils and equipment were treated with concentrations ranging from 1.5 to 4 µg/mL and compared with a conventional chlorine-based disinfectant. Results. The results showed that Argirium SUNc^® was particularly effective in reducing Total Bacterial Count and Enterobacteria, frequently outperforming the traditional disinfectant, especially in the fish sector. In some cases, the bio-gel formulation proved to be more effective, thanks to its greater adhesion to surfaces and prolonged bacteriostatic activity. Conclusions. In conclusion, Argirium SUNc^® represents a sustainable antimicrobial solution that is effective at low concentrations, biocompatible and free of additional chemicals. In addition to improving the hygienic quality of food surfaces, it offers a concrete alternative to traditional disinfectants, contributing to the reduction of the risk of spreading resistant bacterial strains. Thanks to its unique characteristics, this technology lends itself to further developments in the veterinary and zootechnical fields and in the production of active packaging materials. The use of Argirium SUNc^® could be an important innovation in food industry sanitation programmes, with positive repercussions on product safety and public health. This work, funded by the Ministry of Health as part of its veterinary public health and food safety activities, is part of the IZSME 01/21 Current Research project.