Proton (H) NMR spectroscopy presents a powerful tool for biomass mixture studies by revealing the involved chemical compounds with identified ingredients and molecular structures. However, conventional H NMR generally suffers from spectral congestion when measuring biomass mixtures, particularly biomass carbohydrate samples, that contain various physically and chemically similar compounds. In this study, a targeted detection NMR approach, DREAMTIME, is exploited for studying biomass carbohydrate mixtures by spectroscopically targeting the desired compounds in separate 1D NMR spectra.
View Article and Find Full Text PDFSelective homonuclear proton correlation NMR spectroscopy (COSY) provides a useful detection tool for elucidating molecular structures and identifying chemical compositions in 1D spectroscopic patterns. However, conventional 1D selective COSY experiments highly rely on the performance of selective excitation on targeted signals and their applications generally suffer from spectral congestion in complex chemical and biological samples. Herein, based on the concept of targeted excitation on coupled proton pairs and spectroscopic separation on their respective COSY responses, we propose a 1D selective NMR approach that is capable of individually recording direct coupling correlation information of targeted proton groups for analyses on complex samples, free of spectral congestion.
View Article and Find Full Text PDFLaplace NMR is a powerful tool for studying molecular dynamics and spin interactions, providing diffusion and relaxation information that complements Fourier NMR used for composition determination and structure elucidation. However, Laplace NMR demands sophisticated signal processing algorithms such as inverse Laplace transform (ILT). Due to the inherently ill-posed nature of ILT problems, it is generally challenging to perform satisfactory Laplace NMR processing and reconstruction, particularly for two-dimensional Laplace NMR.
View Article and Find Full Text PDFProton magnetic resonance spectroscopy (H MRS) presents a powerful tool for revealing molecular-level metabolite information, complementary to the anatomical insight delivered by magnetic resonance imaging (MRI), thus playing a significant role in in vivo/in vitro biological studies. However, its further applications are generally confined by spectral congestion caused by numerous biological metabolites contained within the limited proton frequency range. Herein, we propose a pure-shift-based H localized MRS method as a proof of concept for high-resolution studies of biological samples.
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