“…Therefore, the hybridisation processes can take place in solution, which means that they are thermodynamically favourable when compared to solid-phase processes [ [17] , [18] , [19] ]. To achieve this, we used PS-NPs due to their robustness and stability in the biological environment, and their compatibility with standard multistep chemistries, allowing different orthogonal conjugation strategies [ [20] , [21] , [22] , [23] , [24] , [25] , [26] ]. The novel PS-NPs used in this work are bifunctionalised containing both a streptavidin as the high-affinity partner of biotin, and a fluorophore (5(6)-carboxyfluorescein, -FAM-) as tracker.…”