“…Nevertheless, the preparation of selective chemosensors, especially for detection, quantification, and/or removal of anions from polluted waters, is still challenging [ 4 , 5 , 6 , 7 , 8 , 9 , 10 ]. The recognition of a specific anion by a receptor can induce a response, being it an electrochemical or optical transition (e.g., color change or fluorescence ON/OFF), that can be used to monitor the presence and, in some cases, the concentration of an anionic guest [ 11 , 12 ]. This performance is predominantly useful for the detection of environmentally harmful anions (e.g., nitrate and phosphate) [ 13 , 14 ], detection of potentially toxic anions (e.g., cyanide) [ 15 ], or in medical diagnostics [ 16 ].…”