A Mini Review on Carbazole Fluoroscent Chemosensors for the Detection of Cu (II) Ion: A Comprehensive Review.

The first fluorescent chemosensor was introduced by F. Goppelsröder (1867) for the detection of Al (III) ion through the formation of strongly fluorescent chelate of morin ion. This mini review focuses on carbazole derivatives fluorescence for detecting Cu²⁺ ions in aqueous and living systems. Carbazole is an example of heterocyclic compound containing nitrogen atom. Carbazole and its derivatives have been used as fluorescent sensors for the detection of Cu²⁺ ions due to the some inherent features such as high solubility, presence of large conjugated system, active intramolecular charge transfer capability, reasonable thermal resistance, photochemical useful, photoelectric properties, and bioactive efficiencies. These features make carbazole and its derivatives effective for applications in fluorescent sensing, photoelectric devices, dyes, molecular recognition, and pharmaceuticals. Different photophysical mechanisms such as chelation enhanced fluorescence (CHEF), intramolecular charge transfer (ICT), photoinduced electron transfer (PET), aggregation induced emission (AIE) play important role in the detection of Cu²⁺ ions while using fluorescent sensors. This review also highlighted on various methods of synthesis of carbazole in brief. The work done on the applications of carbazole fluorescent during the period 2013 to till date has been summarized in tabular form.