PHOTOEMISSION ANALYSIS OF CHEMICAL DIFFERENCES BETWEEN THE MEMBRANE AND CYTOPLASM OF NEURONAL CELLS

We demonstrate the possibility of using x-ray photoemission spectrosco py (XPS) to distinguish between the chemical properties of the neuron membrane and of the cytoplasm in brain cells. This was possible by ana lysing cells de-capped by using a newly developed technique. The XPS s pectra clearly show chemical differences between the cell cytoplasm an d the membrane, for example between nitrogen in -NH2 and -NH3, which a re characteristic of the proteins and membrane phospholipids, respecti vely. A preliminary (and not conclusive) interpretation of all the obs erved spectroscopic features is given.