title: Fluorescence characteristics of 5-amino salicylic acid: An iodide recognition study.
abstract: In this paper we report the effect of iodide on the fluorescence of 5-amino salicylic acid (5-ASA). In the absence of iodide, prominent blue green (BG) emission band at ∼465nm (broad) is observed in aprotic solvents whereas violet (V) emission at ∼408nm, blue green (BG) at ∼480nm and green (G) at ∼500nm are observed in case of protic solvents. On the addition of iodide ion (I(-)), the intensity of BG fluorescence is enhanced in case of aprotic solvents. On the other hand the G band is enhanced in protic solvents and decrease in the intensity of the V band is observed. The effect of hydrogen bonding as well as the interplay of neutral and ionic species is invoked to explain the observed results. The study projects the application of this system in iodide recognition in protic/aprotic environments.
authors.affiliation: Photophysics Laboratory, Department of Physics, DSB Campus, Kumaun University, Nainital 263002, India.
authors.forename: Priyanka
authors.initials: P
authors.lastname: Arora
authors.forename: Kanchan
authors.initials: K
authors.lastname: Suyal
authors.forename: Neeraj K
authors.initials: NK
authors.lastname: Joshi
authors.forename: Hem Chandra
authors.initials: HC
authors.lastname: Joshi
authors.forename: Sanjay
authors.initials: S
authors.lastname: Pant
mesh_terms: D000042:Absorption; D000097:Acetonitriles / Q000737:chemistry; D004126:Dimethylformamide / Q000737:chemistry; D007454:Iodides / Q000737:chemistry*; D019804:Mesalamine / Q000737:chemistry*; D000432:Methanol / Q000737:chemistry; D011193:Potassium Iodide / Q000737:chemistry; D012997:Solvents / Q000737:chemistry; D013050:Spectrometry, Fluorescence
chemical_list: D000097:Acetonitriles; D007454:Iodides; D012997:Solvents; D011193:Potassium Iodide; D019804:Mesalamine; D004126:Dimethylformamide; D000432:Methanol; C032159:acetonitrile