Photophysics of 2-(4'-N,N-dimethylaminophenyl)imidazo[4,5-b]pyridine in micelles: selective dual fluorescence in sodium dodecylsulphate and Triton X-100.
The photophysical behavior of 2-(4'-N,N-dimethylaminophenyl)imidazo[4,5-b]pyridine (DMAPIP-b) has been studied in nonionic triton X-100 (TX-100), cationic cetyltrimethylammonium bromide (CTAB) and anionic sodium dodecylsulfate (SDS) micelles using steady state and time resolved fluorescence techniques. The molecule emits both normal and TICT fluorescence in SDS and TX-100 but emits only normal fluorescence in CTAB. This difference in behavior of the fluorophore is due to varying extent of hydrogen bonding experience by it in different micelles. Of the three possible monocations, only two kinds of monocations, MC1 (formed by protonation of pyridine ring nitrogen) and MC2 (formed by the protonation of imidazole nitrogen) are present in all the micelles (Scheme 1). DFT calculations performed on the monocations reveal that MC1 and MC2 are more stable than MC3, the monocation formed by the protonation of dimethylamino nitrogen.
Dash
Nihar
N
Department of Chemistry, Indian Institute of Technology Guwahati, Guwahati 781039, India.
Krishnamoorthy
G
G
D000042:Absorption; D001665:Binding Sites; D000077286:Cetrimonium; D002593:Cetrimonium Compounds / Q000737:chemistry; D004579:Electron Transport; D005456:Fluorescent Dyes / Q000737:chemistry; D006863:Hydrogen-Ion Concentration; D007093:Imidazoles / Q000737:chemistry*; D008823:Micelles; D017830:Octoxynol / Q000737:chemistry*; D011725:Pyridines / Q000737:chemistry*; D012967:Sodium Dodecyl Sulfate / Q000737:chemistry*; D013050:Spectrometry, Fluorescence; D013997:Time Factors
C549150:2-(4'-N,N-dimethylaminophenyl)imidazo(4,5-b)pyridine; D002593:Cetrimonium Compounds; D005456:Fluorescent Dyes; D007093:Imidazoles; D008823:Micelles; D011725:Pyridines; D012967:Sodium Dodecyl Sulfate; D017830:Octoxynol; D000077286:Cetrimonium
Chem Rev. 2003 Oct;103(10):3899-4032
14531716
Phys Rev B Condens Matter. 1988 Jan 15;37(2):785-789
9944570
Biochim Biophys Acta. 2002 Jun 13;1563(1-2):35-44
12007623
J Phys Chem B. 2008 Jun 19;112(24):7211-9
18503274
J Phys Chem B. 2008 Mar 13;112(10):2868-73
18278903
J Colloid Interface Sci. 2008 Sep 1;325(1):236-42
18538335
J Phys Chem B. 2007 Nov 15;111(45):12985-92
17958349
Colloids Surf B Biointerfaces. 2008 Oct 1;66(1):103-9
18621510
J Colloid Interface Sci. 1999 May 1;213(1):53-61
10191006
J Phys Chem B. 2008 Mar 27;112(12):3684-92
18307338
J Org Chem. 1999 Sep 3;64(18):6566-6574
11674658
J Phys Chem B. 2008 Jun 19;112(24):7338-44
18503268