ADENINE IN MINERAL SAMPLES: DEVELOPMENT OF A METHODOLOGY BASED ON SURFACE ENHANCED RAMAN AND RAMAN MICROSCOPY FOR PICOMOLE DETECTION

摘要

Study of interactions of biological macromolecules with mineral surfaces are of crucial interest either for understanding primeval metabolic processes and for detection of traces of living activities. The development of rational methodologies based on mineral models to which controlled amounts of nucleic acids or monomers are added, is thus needed. Another stake is to detect the smallest quantities. Surface Enhanced Raman spectroscopy (SERS) and Raman microscopy are techniques of choice to study samples slightly concentrated - one can detect 10~(-12) moles ―. SERS also gives information on the structure of molecules adsorbed on an adapted surface, as silver. We present here results concerning the adsorption and detection of the adenine nucleic base on clay. Results show that a combination of SERS effect and Raman microscopy is essential for an optimal detection up to 10~(-3) picomoles.