A nano technology-based synthetic DNA-labelled colloidal tracer was tested for the first time in a fractured calcarenite in the Northern Apennines (Italy). The analytical procedure is based upon the qPCR protocol. The results of the application, carried out by an interdisciplinary research group of hydrogeologists and molecular biologists from the University of Bologna (led by Prof. Alessandro Gargini), has now been published in Hydrogeology Journal https://doi.org/10.1007/s10040-025-02939-7. A mass of 0.5 mg of silica-encapsulated nanoparticles was injected inside a borehole and recovered from two spring-boxes and another borehole downgradient of the injection site. The breakthrough curve signal highlighted the role of open fractures as preferential flow pathways traced by the particles with an effective average groundwater velocity in the range of 100-1000 m/d. The very low detection limit of the tracer and its aptitude to be transported in a conservative way in fractures and other conduits makes it an ideal tool to anticipate or verify hydrogeological connections between man-made tunnels and receptors, such as springs or groundwater dependent ecosystems.
Prof. Alessandro Gargini and Ernesto Pugliese (IAH Members)
