Fluorescence response of hypocrellin B to the environmental changes in a mimic biological membrane——liposome  

作　　者：JIN Xuanye1,2, ZHAO Yuewei1, XIE Jie1 & ZHAO Jingquan1 1. CAS Key Laboratory of Photochemistry, Center for Molecular Science, Institute of Chemistry, Chinese Academy of Science, Beijing 100080, China 2. School of Earth Sciences and Resources, China University of Geosciences, Beijing 100083, China 

出　　处：《Science China Chemistry》2004年第4期335-339,共5页中国科学（化学英文版）

基　　金：This work was supported by the National Natural Science Foundation of China(Grant No.20273079).

摘　　要：Liposome is well known as not only a drug-delivery system but also a simple model for biological membranes. It was reported that fluorescence properties of hypocrellins were changeable over some extreme pH values. In the current work, the effects of the microenvironments on the fluorescence properties of HB in liposome, including approximately physiological range of pH values pH = 6.0-8.0, concentration of cholesterols and ionic strength of the solution, were studied. It was found that the fluorescence intensity of HB was sensitive to and also regulated by the microenvironments. When concentration of cholesterols and ionic strength keep invariable in PBS solution, there exists the maximum for the fluorescence of HB-liposome at pH 7.4 while the minimum for that of HB at pH 7.0. In addition, when pH value keeps constant (7.2), there exists the maximum at the ionic strength of 0.12 mol/kg while that at the concentration of 6×10?4 mol/L for cholesterols. On the other hand, in PBS solution, the lower the ionic strength is, the higher the fluorescence intensity is. The environment-sensitive fluorescence may be potentially applicable to probe some specific environmental features in cells or tissues.Liposome is well known as not only a drug-delivery system but also a simple model for biological membranes. It was reported that fluorescence properties of hypocrellins were changeable over some extreme pH values. In the current work, the effects of the microenviron-ments on the fluorescence properties of HB in liposome, including approximately physiological range of pH values pH = 6.0—8.0, concentration of cholesterols and ionic strength of the solution, were studied. It was found that the fluorescence intensity of HB was sensitive to and also regulated by the microenvironments. When concentration of cholesterols and ionic strength keep invariable in PBS solution, there exists the maximum for the fluorescence of HB-liposome at pH 7.4 while the minimum for that of HB at pH 7.0. In addition, when pH value keeps constant (7.2), there exists the maximum at the ionic strength of 0.12 mol/kg while that at the concentra-tion of 6?0-4 mol/L for cholesterols. On the other hand, in PBS solution, the lower the ionic strength is, the higher the fluorescence intensity is. The environment-sensitive fluorescence may be potentially applicable to probe some specific environmental features in cells or tissues.

关 键 词：MICROENVIRONMENT hypocrellin B liposome fluorescence 

分 类 号：O629[理学—有机化学]