The interaction of indocyanine green（ICG） with human serum albumin（HSA） was investigated via various spectrometric（UV-visible, fluorescence and circular dichroism） techniques. The experimental results indicate t...The interaction of indocyanine green（ICG） with human serum albumin（HSA） was investigated via various spectrometric（UV-visible, fluorescence and circular dichroism） techniques. The experimental results indicate that the interaction of ICG with HSA depends on the values of R（R is defined as the molar ratio of HSA to ICG）. The interaction of 1CG with HSA can form two complexes with intrinsic binding constants（Ka） of 2.97×105（R≤2） and 2.63×104（R〉2）, respectively. The fluorescence and induced CD（ICD） spectra of ICG demonstrate that binding the first mole of HSA to ICG can form a chiral ICG-HSA complex with strong fluorescence emission, and the chirality and fluorescence of ICG-HSA complex can be significantly reduced by adding another mole of HSA to 1CG. Furthermore, although both ICG and ICG-HSA complexes followed an energy-dependent endocytosis process to enter living cells, the cellular uptaken dynamic mechanism of ICG was significantly affected by the HSA conjugation.展开更多
基金Supported by the National Natural Science Foundation of China（No.81571737） and the Project of the Jilin Provincial Science and Technology Department, China（Nos.20130204028GX, 20140413037GH）.
文摘The interaction of indocyanine green（ICG） with human serum albumin（HSA） was investigated via various spectrometric（UV-visible, fluorescence and circular dichroism） techniques. The experimental results indicate that the interaction of ICG with HSA depends on the values of R（R is defined as the molar ratio of HSA to ICG）. The interaction of 1CG with HSA can form two complexes with intrinsic binding constants（Ka） of 2.97×105（R≤2） and 2.63×104（R〉2）, respectively. The fluorescence and induced CD（ICD） spectra of ICG demonstrate that binding the first mole of HSA to ICG can form a chiral ICG-HSA complex with strong fluorescence emission, and the chirality and fluorescence of ICG-HSA complex can be significantly reduced by adding another mole of HSA to 1CG. Furthermore, although both ICG and ICG-HSA complexes followed an energy-dependent endocytosis process to enter living cells, the cellular uptaken dynamic mechanism of ICG was significantly affected by the HSA conjugation.
