Wisser Dorothea, Brückner Stephan I, Wisser Florian M, Althoff-Ospelt Gerhard, Getzschmann Jürgen, Kaskel Stefan, Brunner Eike
Bioanalytical Chemistry, Technische Universität Dresden, 01062 Dresden, Germany.
Inorganic Chemistry I, Technische Universität Dresden, 01062 Dresden, Germany.
Solid State Nucl Magn Reson. 2015 Apr-May;66-67:33-39. doi: 10.1016/j.ssnmr.2014.12.007. Epub 2015 Jan 5.
Triple resonance solid-state NMR experiments using the spin combination (1)H-(13)C-(29)Si are still rarely found in the literature. This is due to the low natural abundance of the two heteronuclei. Such experiments are, however, increasingly important to study hybrid materials such as biosilica and others. A suitable model substance, ideally labeled with both (13)C and (29)Si, is thus very useful to optimize the experiments before applying them to studies of more complex samples such as biosilica. Tetraphenoxysilane could be synthesized in an easy, two-step synthesis including double isotope labelling. Using tetraphenoxysilane, we established a (1)H-(13)C-(29)Si double CP-based HETCOR experiment and applied it to diatom biosilica from the diatom species Thalassiosira pseudonana. Furthermore, we carried out (1)H-(13)C{(29)Si} CP-REDOR experiments in order to estimate the distance between the organic matrix and the biosilica. Our experiments on diatom biosilica strongly indicate a close contact between polyamine-containing parts of the organic matrix and the silica. This corroborates the assumption that the organic matrix is essential for the control of the cell wall formation.
使用自旋组合（1）H - （13）C - （29）Si的三共振固态核磁共振实验在文献中仍然很少见。这是由于两种异核的天然丰度较低。然而，此类实验对于研究诸如生物二氧化硅等杂化材料变得越来越重要。因此，一种合适的模型物质，理想情况下同时用（13）C和（29）Si标记，对于在将实验应用于研究更复杂的样品（如生物二氧化硅）之前优化实验非常有用。四苯氧基硅烷可以通过简单的两步合成法合成，包括双重同位素标记。使用四苯氧基硅烷，我们建立了基于（1）H - （13）C - （29）Si双交叉极化的异核多量子相干实验，并将其应用于来自硅藻物种拟菱形藻的硅藻生物二氧化硅。此外，我们进行了（1）H - （13）C{(29)Si}交叉极化旋转回波双共振实验，以估计有机基质与生物二氧化硅之间的距离。我们对硅藻生物二氧化硅的实验强烈表明，有机基质中含多胺部分与二氧化硅之间存在紧密接触。这证实了有机基质对于控制细胞壁形成至关重要的假设。
