Study on chemical forms of aluminum in tea leaves using micro-PIXE method

Elemental analysis of the epidermis of tea leaves was performed using the micro-beam particle-induced X-ray emission (micro-PIXE) method. The ratios of the X-ray yields of silicon (Si), potassium (K), calcium (Ca), and manganese (Mn) to that of aluminum (Al) in the cell wall of epidermal cells of tea leaves were determined. The ratio of Si to Al X-ray yields agreed within a range of 11% in the four samples measured in this study. On the other hand, the ratio of the X-ray yields of K, Ca, and Mn to Al varied from 41% to 87%. This result suggests that Al forms compounds with Si in tea leaves.