PIXE ANALYSIS OF PLANT-LEAVES OF DOMESTIC USE IN MEXICO

A quantitative PIXE method - based on an external beam facility - appl icable to plant samples, is described in this work, along with the res ults obtained from the elemental analysis of leaves from nine differen t plants, commonly used for curative purposes in Mexico. At room condi tions, pellet formed samples from the leaves were irradiated with 3.55 MeV protons. A computer code called PIXCO, allowed us: a) to evaluate (and optimize) the experimental conditions previous to the irradiatio ns, b) to obtain the Si(Li) detector efficiency calibration and, c) to transform the net areas of the characteristic X-ray peaks into absolu te concentrations, considering the relevant physical parameters and st atistical tests pertinent to a thick sample analysis. A sample doping procedure was followed to avoid problems related with beam charge inte gration, and with the aid of a proper reference material (IAEA standar d), a calibration of the system was acquainted for. The concentrations obtained, have an estimated precision of less than 15% for most of th e elements analyzed.