Abstract: Non aqueous solvents or mixtures for DNP NMR spectroscopy, method to prepare said solvents or mixtures and use of said solvents or mixtures The present invention concerns a method to determine the efficiency of a solvent to impregnate a sample material for use in a dynamic nuclear polarization (DNP) nuclear magnetic resonance (NMR) experiments, characterized in that the method comprising: —selecting a non-aqueous solvent, —providing a polarizing agent that is soluble in the non-aqueous solvent, —dissolving the polarizing agent in the non-aqueous solvent, —impregnating or dissolving the sample material with the non-aqueous solvent containing the polarizing agent, —performing a solid state DNP NMR experiment on the impregnated sample material, —determining a DNP enhancement factor of the DNP NMR experiment.

Abstract: The present invention concerns materials consisting in a porous and structured network, this network being at least in part formed by Si atoms, or Si atoms and metal atoms, linked to each other's via siloxy bonds, the amount of radical ranging from 0.50 to 0.03 mmol of radical per gram of material, and in that the network is formed with a sol-gel step using an organosilane for the introduction of the organic molecules allowing their regular distribution within the porous structured material. The invention also concern a process for the preparation of such material and a method of analysis by Nuclear Magnetic Resonance (NMR) of an analyte wherein it uses dynamic nuclear polarization generated with a material according to the invention.