Papers by Christian Bonhomme
Magnetic resonance, Aug 20, 2021
The spectroscopic study of pathological calcifications (including kidney stones) is extremely ric... more The spectroscopic study of pathological calcifications (including kidney stones) is extremely rich and helps to improve the understanding of the physical and chemical processes associated with their formation. While Fourier transform infrared (FTIR) imaging and optical/electron microscopies are routine techniques in hospitals, there has been a dearth of solid-state NMR studies introduced into this area of medical research, probably due to the scarcity of this analytical technique in hospital facilities. This work introduces effective multinuclear and multidimensional solid-state NMR methodologies to study the complex chemical and structural properties characterizing kidney stone composition. As a basis for comparison, three hydrates (n = 1, 2 and 3) of calcium oxalate are examined along with nine representative kidney stones. The multinuclear magic angle spinning (MAS) NMR approach adopted investigates the 1 H, 13 C, 31 P and 31 P nuclei, with the 1 H and 13 C MAS NMR data able to be readily deconvoluted into the constituent elements associated with the different oxalates and organics present. For the first time, the full interpretation of highly resolved 1 H NMR spectra is presented for the three hydrates, based on the structure and local dynamics. The corresponding 31 P MAS NMR data indicates the presence of low-level inorganic phosphate species; however, the complexity of these data make the precise identification of the phases difficult to assign. This work provides physicians, urologists and nephrologists with additional avenues of spectroscopic investigation to interrogate this complex medical dilemma that requires real, multitechnique approaches to generate effective outcomes.
CrystEngComm, 2013
Multinuclear solid state NMR (including 43 Ca NMR), in combination with DFT calculations, is appl... more Multinuclear solid state NMR (including 43 Ca NMR), in combination with DFT calculations, is applied to the study of the crystal structure of whewellite, CaC 2 O 4 ·H 2 O. This particular hydrated calcium oxalate is of paramount importance as it corresponds to a major phase present in urinary stones. 43 Ca MAS NMR experiments and GIPAW calculations were performed in order to further refine neutron diffraction data. The sensitivity of 43 Ca NMR as a structural probe is demonstrated. This is the first step for the full description of calcium oxalates at the DFT level and the characterization of interfaces between these biomineral phases and organic phases. † Electronic supplementary information (ESI) available: Powder XRD patterns of (a) synthetic whewellite, CaC 2 O 4 .H 2 O, (b) a mixture of whewellite, CaC 2 O 4 . H 2 O and weddellite, CaC 2 O 4 ·2H 2 O (obtained by precipitation). Cell parameters and bond lengths after DFT optimization of the whewellite structure. Simulated XRD powder patterns of the optimized models. GIPAW data for all structural models. See
The synthesis and characterization of the first crystalline structures involving boronate ligands... more The synthesis and characterization of the first crystalline structures involving boronate ligands (PhB(OH)3−) bound to alkaline earth metal cations (Ca2+, Sr2+, Ba2+) are described. Their complete structure determination was made possible using a combination of X-ray diffraction, DFT modeling, and high resolution multinuclear solid-state NMR.
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Papers by Christian Bonhomme