[Comparison of infrared spectroscopy between native and binding metals' phytoplankton]

Infrared spectroscopy of native and metalbinding duckweed was compared. After binding metals, the absorbance peak around 3,400 cm-1, which reflects OH group stretching vibration, had been moved about 83 cm-1, and its absorbance was decreased. The absorbance of the dominating bands near 1,650 and 1,540 cm-1, the characteristic IR absorption of protein, was decreased. Therefore, the peak absorbance at 620 cm-1 was increased significantly by exposure to high concentration of ZnSO4 solution. So we concluded that OH group play a important role in binding zinc cation and the structure of cell walls had changed due to zinc existing. Furthermore, the process of binding metals by duckweed is physical adsorption and chemical adsorption simultaneously.