Investigation of the Microenvironment of Novel Amphiphilic Dendrimers with Nile Red as a Probe

doi:10.7517/j.issn.1674-0475.2010.05.343

Abstract

Abstract: Amphiphilic poly(alkyl aryl ether) dendrimers with tetraethylene glycol monomethyl ether at their periphery(Gn,n=0—3),were synthesized by a convergent growth methodology and their structures were characterized by ¹H NMR,IR and mass spectroscopy(MALDI-TOF).The microenvironment of these dendrimers was studied by using Nile Red as a fluorescence probe.The absorption spectra of Nile Red in water and Gn aqueous solutions indicate that the solubility of Nile Red increases dramatically with the increase of dendrimer generation.The steady state and time resolved fluorescence studies reveal that the microenvironment polarity of Gn(n=1—3) decreases with the increase of dendrimer generation.G1 and G2 dendrimers have similar microenvironment polarity,while G3 has a more hydrophobic inner cavity due to its globular structure.

Key words: dendrimer, microenvironment polarity, fluorescence spectra, nile red

CLC Number:

YUAN Zhao, ZENG Yi, CHEN Jin-ping, LI Ying-ying, HAN Yong-bin, LI Yi. Investigation of the Microenvironment of Novel Amphiphilic Dendrimers with Nile Red as a Probe[J]. Imaging Science and Photochemistry, 2010, 28(5): 343-353.

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