title: Aggregation induced emission enhancement (AIEE) characteristics of quinoline based compound - A versatile fluorescent probe for pH, Fe(III) ion, BSA binding and optical cell imaging.
abstract: Novel benzimidazoquinoline derivative (AVT) was synthesized through a substitution reaction and characterized by various spectral techniques. Analyzing the optical properties of AVT under absorption and emission spectral studies in different environments exclusively with respect to solvents and pH, intriguing characteristics viz. aggregation induced emission enhancement (AIEE) in the THF solvent and 'On-Off' pH sensing were found at neutral pH. Sensing nature of AVT with diverse metal ions and bovine serum albumin (BSA) was also studied. Among the metal ions, Fe3+ion alone tunes the fluorescence intensity of AVT probe in aqueous medium from "turn-on" to "turn-off" through ligand (probe) to metal charge transfer (LMCT) mechanism. The probe AVT in aqueous medium interacts strongly with BSA due to Fluorescence Resonance Energy Transfer (FRET) and the conformational change in BSA was further analyzed using synchronous fluorescence techniques. Docking study of AVT with BSA reveals that the active site of binding is tryptophan residue which is also supported by the experimental results. Interestingly, fluorescent AVT probe in cells was examined through cellular imaging studies using BT-549 and MDA-MB-231 cells. Thus, the single molecule probe based detection of multiple species and stimuli were described.
authors.affiliation: Department of Chemistry, Bannari Amman Institute of Technology, Sathymangalam 638 401, India.
authors.forename: Irulappan
authors.initials: I
authors.lastname: Manikandan
authors.affiliation: Institute of Chemistry, Academia Sinica, Taipei 115, Taiwan.
authors.forename: Chien-Huei
authors.initials: CH
authors.lastname: Chang
authors.affiliation: Institute of Chemistry, Academia Sinica, Taipei 115, Taiwan.
authors.forename: Chia-Ling
authors.initials: CL
authors.lastname: Chen
authors.affiliation: Department of Chemistry, Bannari Amman Institute of Technology, Sathymangalam 638 401, India.
authors.forename: Veerasamy
authors.initials: V
authors.lastname: Sathish
authors.affiliation: Institute of Chemistry, Academia Sinica, Taipei 115, Taiwan; Doctoral Degree Program in Marine Biotechnology, National Sun Yat-Sen University, Kaohsiung 804, Taiwan. Electronic address: wenshan@gate.sinica.edu.tw.
authors.forename: Wen-Shan
authors.initials: WS
authors.lastname: Li
authors.affiliation: Department of Chemistry, Bannari Amman Institute of Technology, Sathymangalam 638 401, India. Electronic address: malathimahalingamm@bitsathy.ac.in.
authors.forename: Mahalingam
authors.initials: M
authors.lastname: Malathi
mesh_terms: D045744:Cell Line, Tumor; D003584:Cytological Techniques / Q000379:methods*; D005290:Ferric Compounds / Q000032:analysis* / Q000737:chemistry; D031541:Fluorescence Resonance Energy Transfer / Q000379:methods*; D005456:Fluorescent Dyes / Q000032:analysis / Q000737:chemistry* / Q000633:toxicity; D006801:Humans; D006863:Hydrogen-Ion Concentration; D015335:Molecular Probes / Q000032:analysis / Q000737:chemistry* / Q000633:toxicity; D011485:Protein Binding; D011804:Quinolines / Q000032:analysis / Q000737:chemistry* / Q000633:toxicity; D012710:Serum Albumin, Bovine / Q000032:analysis / Q000737:chemistry; D013056:Spectrophotometry, Ultraviolet
chemical_list: D005290:Ferric Compounds; D005456:Fluorescent Dyes; D015335:Molecular Probes; D011804:Quinolines; D012710:Serum Albumin, Bovine
keywords: Aggregation induced emission enhancement; BSA binding; Cell imaging; Fe(III) ion sensor; pH sensor