Modernization of the NMR Laboratory of the UNICAMP, Institute of Chemistry: acquisition of a 600-MHz spectrometer for experiments in solution

Abstract

The aim of this proposal is the acquisition of a nuclear magnetic resonance (NMR) spectrometer for obtaining data related to the molecular structure of compounds in solution. Although we intend to employ well-known and widely used NMR techniques, we also plan to correlate the basic NMR parameters, especially coupling constants, with the molecular electronic structure. To that end, we will use modern NMR techniques, some of which will have to be modified in order to adapt them to our needs. This will make it possible to determine the heteronuclear coupling constants with precision. Therefore, it is of utmost importance to acquire a spectrometer with a high magnetic field (14 Tesla), which allows various data to be obtained in less time, thus avoiding problems of resolution and sensitivity. This equipment will be also employed for the following: measurements of spin diffusion in the separation and identification of components in complex mixtures; measurements of longitudinal and transversal relaxation (T1 and T2, respectively), for studying solvation and intermolecular chemical exchanges between solutes and solvents; and to determine the porosity of carbonate rock samples impregnated with oil, for obtaining the distribution of pores in reservoir rocks by quantifying proton relaxation within the oil molecules. It will also be possible to obtain images derived from NMR signals in heterogeneous systems, such as emulsions, in order to study their interphases. In addition, we will be able to employ the saturation transfer difference technique, characterizing the epitope of certain enzymes with small molecules (cofactors or inhibitors), in order to clarify the interactions with the enzymes that participate in specific cellular processes. Finally, the spectrometer will be used by research groups responsible for complementary Institute of Chemistry projects, but will also be made accessible to any other qualified researchers, whether working at the Institute of Chemistry or at other institutions in the State of São Paulo, for structural analyses and for other experiments that require high-field equipment. (AU)