Recent applications of quantitative nuclear magnetic resonance spectroscopy in pharmaceutical research

Rackham, David M.

doi:10.1016/0039-9140(76)80192-0

Cited by 29 publications

(16 citation statements)

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“…NMR can be used to analyze samples that are in liquid state, solid state, or something between the two (such as tissues, gels, cells, etc.). [ 2–9 ] Its intrinsic quantitative nature is increasingly being exploited in areas ranging from complex mixture analysis (as in metabolomics, food sciences, and reaction monitoring), to Quality Assurance/Control (QA/QC). A recent review on quantitative NMR [ 10 ] comprehensively discusses its unique and robust nature in a variety of applications.…”

Section: Introductionmentioning

confidence: 99%

Complete Reduction to Amplitude Frequency Table (CRAFT)—A perspective

Krishnamurthy¹

2021

Magnetic Reson in Chemistry

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The CRAFT (Complete Reduction to Amplitude Frequency Table) technique, based on Bayesian analysis approach, converts FID and/or interferogram (time domain) to a frequency‐amplitude table (tabular domain) in a robust, automated, and time‐efficient fashion. This mini review/perspective presents an introduction to CRAFT as a processing workflow followed by a discussion of several practical 1D and 2D examples of its applicability and associated benefit. CRAFT provides high quality quantitative results for complex systems without any need for conventional preprocessing steps, such as phase and baseline corrections. Two‐dimensional time domain data are typically truncated, particularly in the evolution dimension, and conventional processing after zero‐filling and t1max‐matched apodization masks potentially available peak resolution. The line broadening introduced by extensive zero‐filling and severe apodization functions leads to the lack of clear resolution of cross peaks. CRAFT decimation of interferograms, on the other hand, requires minimal or no apodization prior to extraction of the NMR parameters and significantly improves the spectral linewidth of the cross peaks along F1 dimension compared to conventional (FT) processing. The tabular representation of the CRAFT2d cross peaks information can be visualized in a variety of frequency domain formats for conventional spectral interpretation as well as quantitative applications. A simple workflow to generate in silico oversampled interferogram (iSOS) is presented, and its potential benefit in CRAFT decimation of highly crowded 2D NMR is demonstrated. This report is meant as a collective thesis to present a potentially new paradigm in data processing that questions the need for hitherto unchallenged preprocessing steps, such as phase and baseline correction in 1D and zero‐fill/severe apodization in 2D.

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Section: Introductionmentioning

confidence: 99%

Complete Reduction to Amplitude Frequency Table (CRAFT)—A perspective

Krishnamurthy¹

2021

Magnetic Reson in Chemistry

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“…NMR can be used to analyze samples that are in liquid state, solid state, or something between the two (such as tissues, gels, cells, etc.) . NMR spectroscopy also provides a variety of additional experimental techniques to extract detailed structural information from the spectra.…”

Section: Introductionmentioning

confidence: 99%

“…NMR can be used to analyze samples that are in liquid state, solid state, or something between the two (such as tissues, gels, cells, etc.). [1][2][3][4][5][6][7][8] NMR spectroscopy also provides a variety of additional experimental techniques to extract detailed structural information from the spectra. However, complex one-dimensional (1D) NMR spectra that contain many overlapped signals are more common than not.…”

Section: Introductionmentioning

confidence: 99%

CRAFT (complete reduction to amplitude frequency table) – robust and time‐efficient Bayesian approach for quantitative mixture analysis by NMR

Krish

2013

Magnetic Reson in Chemistry

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The intrinsic quantitative nature of NMR is increasingly exploited in areas ranging from complex mixture analysis (as in metabolomics and reaction monitoring) to quality assurance/control. Complex NMR spectra are more common than not, and therefore, extraction of quantitative information generally involves significant prior knowledge and/or operator interaction to characterize resonances of interest. Moreover, in most NMR-based metabolomic experiments, the signals from metabolites are normally present as a mixture of overlapping resonances, making quantification difficult. Time-domain Bayesian approaches have been reported to be better than conventional frequency-domain analysis at identifying subtle changes in signal amplitude. We discuss an approach that exploits Bayesian analysis to achieve a complete reduction to amplitude frequency table (CRAFT) in an automated and time-efficient fashion - thus converting the time-domain FID to a frequency-amplitude table. CRAFT uses a two-step approach to FID analysis. First, the FID is digitally filtered and downsampled to several sub FIDs, and secondly, these sub FIDs are then modeled as sums of decaying sinusoids using the Bayesian approach. CRAFT tables can be used for further data mining of quantitative information using fingerprint chemical shifts of compounds of interest and/or statistical analysis of modulation of chemical quantity in a biological study (metabolomics) or process study (reaction monitoring) or quality assurance/control. The basic principles behind this approach as well as results to evaluate the effectiveness of this approach in mixture analysis are presented.

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“…Over the last two decades, increased utilization of enabling methodology such as Fourier transform infrared spectroscopy (FTIR), ultraviolet-visible spectrophotometry (UV-Vis) and flow chemistry has led to an increases in the number of compounds[4],[5]. This has led to a significant increase in the quantity of analytical data that needs to be reviewed to characterize the toxic pesticides[6]-[10]. Each NMR parameter may play an important role in determining the structure of pesticides.…”

Section: Introductionmentioning

confidence: 99%

Three dimensional structure prediction and proton nuclear magnetic resonance analysis of toxic pesticides in human blood plasma

Sharma¹,

Tiwari²,

Gaur³

2012

J Biomed Res

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The purpose of this study was to investigate the nuclear magnetic resonance (NMR) assignments of hydrolyzed products extracted from human blood plasma. The correlations between chemical, functional and structural properties of highly toxic pesticides were investigated using the PreADME analysis. We observed that toxic pesticides possessed higher molecular weight and, more hydrogen bond donors and acceptors when compared with less toxic pesticides. The occurrence of functional groups and structural properties was analyzed using 1H-NMR. The 1H-NMR spectra of the phosphomethoxy class of pesticides were characterized by methyl resonances at 3.7-3.9 ppm (δ) with the coupling constants of 11-16 Hz (JP-CH3). In phosphoethoxy pesticides, the methyl resonance was about 1.4 ppm (δ) with the coupling constant of 10 Hz (JP-CH2) and the methylene resonances was 4.2-4.4 ppm (δ) with the coupling constant of 0.8 Hz (JP-CH3), respectively. Our study shows that the values of four parameters such as chemical shift, coupling constant, integration and relaxation time correlated with the concentration of toxic pesticides, and can be used to characterise the proton groups in the molecular structures of toxic pesticides.

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Recent applications of quantitative nuclear magnetic resonance spectroscopy in pharmaceutical research

Cited by 29 publications

References 0 publications

Complete Reduction to Amplitude Frequency Table (CRAFT)—A perspective

Complete Reduction to Amplitude Frequency Table (CRAFT)—A perspective

CRAFT (complete reduction to amplitude frequency table) – robust and time‐efficient Bayesian approach for quantitative mixture analysis by NMR

Three dimensional structure prediction and proton nuclear magnetic resonance analysis of toxic pesticides in human blood plasma

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