A Bis-Quinoline Appended Azobenzene Based Naked Eye Sensor for Selective Detection of Cd2+ Ion

A Cu2+ fluorescent chemosensor suitable for quantitative detection of tyrosinase in potatoes over a wide pH range

Cu2+ as an important trace element plays an essential role in various biologic processes due to the unique redox active nature. For this reason, much effort has been made to develop effective methods for Cu2+ detection. In this study, a novel structure fluorescent chemosensor, 1-(6-(((5-(5, 5-difluoro-1, 3, 7, 9-tetramethyl-5H-4λ4, 5λ4-dipyrrolo[1, 2-c:2', 1'-f][1, 3, 2] diazaborinin-10-yl)quinolin-8-yl)oxy)methyl)pyridin-2-yl)-N, N-bis(pyridin-2-ylmethyl)methanamine (1), was synthesized and characterized by 1H and 13C nuclear magnetic resonance spectroscopy, and electrospray ionization mass spectrometry. Sensor 1 showed an obviously "on-off" fluorescence response to Cu2+ with a 1:1 binding stoichiometry by UV-vis and fluorescence spectrophotometry. The detection limit of sensor 1 to Cu2+ was determined to be 1.9 µM, and the stable pH range for Cu2+ detection was from 3 to 13. Sensor 1 can be used for recognition and detection of tyrosinase in potatoes.

8-Hydroxyquinoline Fluorophore for Sensing of Metal Ions and Anions

Among various known hydroxyquinolines, 8-hydroxyquinoline (8-HQ) is the most prevalent moiety due to excellent property for the formation of the complex with different metal ions and anions, and utilized in a wide variety of applications in pharmacological and medicinal fields. 8-Hydroxyquinoline moiety and its analogues acts as fluorophoric ligands on complex formation with alkali and alkaline as well as transition metal ions and anions, thus, considered as an ideal building block in metallo-supramolecular chemistry for recognition, separation, and quantitative investigation of cations. 8-Hydroxyquinoline moiety is also used in various applications for the advancement of novel fluorescent chemosensors in a wide variety of areas viz., material chemistry, bioorganic chemistry, molecular imaging, analytical chemistry, molecular recognition, medical and biological science communities. The present review emphasises on the progress of sensing properties of 8-HQ centred small-molecule fluorescent chemosensors towards several metal ions viz., Fe³⁺ , Al³⁺ , Ag⁺ , Hg²⁺ , Cu²⁺ , Pd²⁺ , Zn²⁺ , Cr³⁺ , Cd²⁺ , Mn²⁺ , Ca²⁺ , and K⁺ and anions such as F^- , CN^- and PPi, from 2008 to 2020, because of their sensitivity and selectivity in terms of diverse colour changes for different species. This critical and comprehensive review might facilitate the improvement of more prevailing chemosensors for future exciting and broad applications.

Corrosion inhibition performance of newly synthesized 5-alkoxymethyl-8-hydroxyquinoline derivatives for carbon steel in 1 M HCl solution: experimental, DFT and Monte Carlo simulation studies

Three new organic compounds primarily based on 8-hydroxyquinoline have been successfully synthesized and characterized via different spectroscopic methods (FTIR, ¹H, and ¹³C NMR).

A pyrazoline-based fluorescent chemosensor for Al3+ ion detection and live cell imaging

The pyrene appended pyrazoline compounds were designed and synthesized for selective detection of Al³⁺ ion.