Fig. 1.

Dendrimer-based potassium nanosensor. Schematic representation of the nanosensor design comprising a generation 5 (poly)amidoamine dendrimer (PAMAM; red) with a 1,4-diaminobutane core (DAB; black). The dendrimer is covalently functionalized with polyethyleneglycol dodecamers (PEG; blue) at its surface for biocompatibility and water solubility. The ${\mathrm{K}}^{+}$-sensitive indicator Asante Potassium Green 4 (APG4) is encapsulated in the dendrimer cavities at a molar ratio of $1:1$.