Affiliations: Analysis & Testing Center, Jiangsu Engineering Research Center for Bio-medical Function Materials, Nanjing Normal University, Nanjing, 210097, P.R. China | School of Life Science, Nanjing Normal University, Nanjing, 210097, P.R. China | Department for intensive instruction, Nanjing Normal University, Nanjing, 210097, P.R. China
Note: [] Corresponding author: Yuying Feng, Professor, Analysis & Testing Center, Jiangsu Engineering Research Center for Bio-medical Function Materials, Nanjing Normal University, 122 Ninghai Road, Nanjing, Jiangsu, 210097, P.R. China. Fax: +86 25 83598359; E-mail: [email protected]
Abstract: Experimental results of UV-visible absorption spectroscopy and fluorescence spectroscopy indicate that hypocrellin A, which has been studied in photodynamic therapy, can interact with the surface of myoglobin through hydrophobic forces, and form a complex. Based on the Stern–Volmer equation, the quenching constants of the process can be calculated to be 4.81×1012 L mol−1 s−1 (t=25°C) and 4.54×1012 L mol−1 s−1 (t=42°C) respectively, and the binding constant is 5.53×104 M−1 (t=25°C), while the binding sites is 0.94 (t=25°C). In addition, Electron paramagnetic resonance and fluorescence spectroscopic analysis suggests that that the quenching mechanism of the interaction process occurs through the electron transfer between hypocrellin A and myoglobin.
Keywords: Hypocrellin A, myoglobin, UV-visible absorption spectroscopy, fluorescence spectroscopy, electron paramagnetic resonance spectroscopy
Journal: Spectroscopy, vol. 21, no. 4, pp. 235-243, 2007
