A lineshape fitting model for ¹H NMR spectra of human blood plasma

Abstract

A lineshape fitting model was constructed for classifying the overlapping information in the 1H NMR spectrum of human blood plasma. A reliable assignment of the overlapping fatty acid (-CH2-)n and -CH3 resonances of the various lipoproteins (VLDL, very low density lipoprotein; LDL, low density lipoprotein; HDL high density lipoprotein) is introduced, and for the first time detailed characteristics (chemical shifts, half linewidths, and relative intensities) of the individual lipoprotein components were obtained directly from the whole plasma spectrum. This was achieved by combining the constructed lineshape fitting model and the proper 400 MHz proton NMR measurements from blood plasma of a healthy donor, from fractions of the different lipoproteins, and from plasma samples in which the lipoprotein fractions were separately added. The results suggest fair promise of future applications of the rapid and easy NMR analysis of lipoprotein distribution in various research and clinical situations.

Line‐shape analysis of J‐resolved NMR spectra: application to metabolomics and quantification of intensity errors from signal processing and high signal congestion

“…Such an approach has been employed successfully for 1D NMR spectra. [23,24] However, unlike for a 1D spectrum in which, under ideal conditions, each resonance is known to have a Lorentzian line-shape, [25] the mathematical function describing a resonance in a processed 2D JRES spectrum has not been thoroughly evaluated. [26] In particular, while investigations into the application of JRES spectra to quantitative analysis have been performed, [27] to the best of our knowledge, the effects of several routine processing steps on the line-shape have not been calculated, including tilting and symmetrising spectra, nor the effects of window functions such as a traditional sine-bell (SINE) and the combined sine-bell -exponential (SEM) function.…”

Original article High resolution proton nuclear magnetic resonance (1H NMR) spectroscopy of surviving C6 glioma cells after X-ray irradiation

“…In order to estimate the lactate resonance area within the methylene lipid 1.18-1.43 ppm range, the methodology proposed by Hiltunen et al for the lipid analysis of blood plasma [18] was adapted. Figure 6 shows the examples of the Lorentz functions fittings within the range of 1.18-1.43 ppm for the non-irradiated cells, the irradiated and incubated ones as well as for the dead cells (acquired two weeks after the embedding in agarose, Fig.…”

“…The CH 2 /CH 3 parameter was calcu lated according to Eq. 1 (the ranges of the lipid bands were selected after Hiltunen et al [18]):…”

“…To determine the contribution of the lactate doublet into the methylene lipid range of 1.18-1.43 ppm, the method proposed by Hiltunen et al [18] for blood plasma was adopted. Taking into account the universality of the lipids in Eucaryota, the method can be applied also to the spectra analysis of the C6 cells.…”

Proton nuclear magnetic resonance lineshape studies on human blood plasma lipids from newborn infants, healthy adults, and adults with tumors

“…[ 31 can be determined to produce the calculated spectrum so close to the experimental NMR spectrum as possible in the x 2 sense. In this work this was done by using the program FITPLA (18), which is based on the Levenberg-Marquardt method to solve the nonlinear matrix equation. A doublet modification was applied to the lactate signals and only one phase parameter to the whole methylene region was used.…”