Effects of Curcumin Concentration and Temperature on the Spectroscopic Properties of Liposomal Curcumin
详细信息 查看全文
- 作者：Yumeng Niu ; Xiaoyong Wang ; Shaohu Chai ; Zhiyun Chen ; Xueqin An ; Weiguo Shen
- 刊名：Journal of Agricultural and Food Chemistry
- 出版年：2012
- 出版时间：February 22, 2012
- 年：2012
- 卷：60
- 期：7
- 页码：1865-1870
- 全文大小：266K
- 年卷期：v.60,no.7(February 22, 2012)
- ISSN：1520-5118
文摘
The spectroscopic properties of liposomal curcumin in pH 7.0 sodium phosphate buffer were studied at various curcumin concentrations and temperatures. At 25 掳C, liposomal curcumin exhibited much higher values than free curcumin in absorption maximum, fluorescence maximum, and fluorescence anisotropy. When curcumin concentration was increased from 2 to 20 渭M, the values of fluorescence anisotropy of liposomal curcumin decreased gradually, consistent with the reduction of phase transition temperature of liposome. This observation revealed that liposomal curcumin can disrupt the packing of phospholipid bilayer and give a loose and disordered structure. On the other hand, as the temperature was increased from 25 to 80 掳C, the relative intensity of maximum absorption of liposomal curcumin showed a more pronounced decrease above the phase transition temperature than lower temperatures, suggesting a weaker curcumin protection from the liquid crystalline phase of phospholipid bilayer than the rigid gel phase. However, it was observed that the fluorescence anisotropy of liposomal curcumin had higher values as the temperature increased. This phenomenon was explained as the result of location change of curcumin toward the core of phospholipid bilayer, although the structure of the phospholipid bilayer tended to be looser at higher temperatures.