Modulated photophysics of an ESIPT probe 1-hydroxy-2-naphthaldehyde within motionally restricted environments of liposome membranes having varying surface charges.
The present work demonstrates the modulation of excited state intramolecular proton transfer (ESIPT) emission of 1-hydroxy-2-naphthaldehyde (HN12) upon its interaction with the liposomal vesicles/bilayer of dimyristoyl-l-α-phosphatidylcholine (DMPC) and dimyristoyl-l-α-phosphatidylglycerol (DMPG) and its subsequent implementation as an efficient molecular reporter for probing of microheterogeneous environments of lipid-bilayer system. Modifications on the emission profile of HN12 in terms of remarkable emission intensity enhancement coupled with a hypsochromic shift induced by the presence of DMPC and DMPG membranes have been interpreted to be vivid manifestations of the interactions between the two partners. Steady-state anisotropy, red-edge excitation shift (REES), and time-resolved fluorescence measurements have been fruitfully exploited to complement other experimental findings. Probable binding site of HN12 in the lipid-bilayers has been assessed on the basis of intertwining the results of fluorescence quenching with other experimental results and is further substantiated from docking studies.
Paul
Bijan Kumar
BK
Department of Chemistry, University of Calcutta, 92 A. P. C. Road, Calcutta-700009, India.
Guchhait
Nikhil
N
D001665:Binding Sites; D003198:Computer Simulation; D004134:Dimyristoylphosphatidylcholine / Q000737:chemistry; D008051:Lipid Bilayers / Q000737:chemistry*; D008081:Liposomes / Q000737:chemistry*; D009284:Naphthols / Q000737:chemistry*; D010715:Phosphatidylglycerols / Q000737:chemistry; D011522:Protons; D013050:Spectrometry, Fluorescence
C555036:1-hydroxy-2-naphthaldehyde; D008051:Lipid Bilayers; D008081:Liposomes; D009284:Naphthols; D010715:Phosphatidylglycerols; D011522:Protons; D004134:Dimyristoylphosphatidylcholine