title: Highly selective fluorescent sensing of fenitrothion using per-6-amino-β-cyclodextrin:Eu(III) complex.
abstract: A unique, efficient, highly sensitive and selective fluorescent chemosensor for fenitrothion has been reported for the first time using per-6-amino-β-cyclodextrin:Eu(III) complex. Among the various pesticides, the sensitivity response is found to be in the order, fenitrothion>>>quinalphos>methylparathion>parathion>methylparaoxon>paraoxon>fenchlorphos>profenofos>malathion. A detection limit as low as 1 × 10(-12)M for fenitrothion sensing is realized with a 2.4% relative standard deviation (RSD) of three consecutive runs. The per-6-amino-β-cyclodextrin:Eu(III):pesticide complexes and their sensing mechanism are evidenced from emission, NMR, FT-IR, binding constant measurement, Job's plot, ICD spectra, ESI-MS, lifetime measurements and molecular modeling studies. The proposed sensing is a consequence of Absorption Energy Transfer Emission (AETE) process as a result of better encapsulation of fenitrothion inside the cavity of per-6-amino-β-cyclodextrin:Eu(III) complex. The remarkable sensitivity and selectivity of fenitrothion compared to other OPs, is attributed to a more deeper binding and tighter fit of fenitrothion inside the CD cavity, which is evident from binding constant values and molecular modeling studies. This tighter fit ensures the replacement of two coordinating water molecules on Eu(III) ion, which may have contributed to the more selective sensing of fenitrothion.
authors.affiliation: School of Chemistry, Madurai Kamaraj University, Madurai 625021, India.
authors.forename: Kuppusamy
authors.initials: K
authors.lastname: Kanagaraj
authors.affiliation: School of Chemistry, Madurai Kamaraj University, Madurai 625021, India.
authors.forename: Abdullah
authors.initials: A
authors.lastname: Affrose
authors.affiliation: School of Chemistry, Madurai Kamaraj University, Madurai 625021, India.
authors.forename: Subbaiah
authors.initials: S
authors.lastname: Sivakolunthu
authors.affiliation: School of Chemistry, Madurai Kamaraj University, Madurai 625021, India. Electronic address: pit12399@yahoo.com.
authors.forename: Kasi
authors.initials: K
authors.lastname: Pitchumani
mesh_terms: D001665:Binding Sites; D015374:Biosensing Techniques / Q000379:methods* / Q000706:statistics & numerical data; D005063:Europium / Q000737:chemistry; D005278:Fenitrothion / Q000032:analysis* / Q000737:chemistry; D005453:Fluorescence; D057230:Limit of Detection; D009943:Organophosphorus Compounds / Q000032:analysis / Q000737:chemistry; D010575:Pesticides / Q000032:analysis* / Q000737:chemistry; D012680:Sensitivity and Specificity; D047392:beta-Cyclodextrins / Q000737:chemistry
chemical_list: D009943:Organophosphorus Compounds; D010575:Pesticides; D047392:beta-Cyclodextrins; C534165:per-6-amino-beta-cyclodextrin; D005063:Europium; D005278:Fenitrothion