Rapid and visual detection of Cd2+ based on aza-BODIPY near infrared dye and its application in real and biological samples for environmental contamination screening.

Cadmium highly toxic and hazardous, and it can adversely affect human health leading to serious disorders. Herein, a water-soluble near-infrared sensor based on aza-BODIPY (1) was developed for dual determination of Cd2+ in environmental and biological media. This sensor exhibited color change from colorless to green along with a fluorescence enhancement in the near-infrared (NIR) region via photoinduced electron transfer (PET) after complexation with Cd2+. Sensor 1 can be employed in aqueous media at physiological pH for quantitative monitoring. It shows rapid response with high sensitivity (detection limit of 2.8 ppb; linear correlation over [Cd2+] 1.33 - 6.67 µM) and selectivity over potentially interfering ions. NIR sensor 1 can be used to determine [Cd2+] in living cells and environmental samples.