ArticleAnalytical chemistry2014
Quantitating metabolites in protein precipitated serum using NMR spectroscopy.
Article in Analytical chemistry, 2014. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Cited by 112 papers, 1 of them a synthesis that pooled it.
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Who cites it
112 citing papers in PubMed, 1 synthesis or guideline pooled it, 235 citations in OpenAlex.
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- Cytoprotective Compounds in the Primate Eye: Baseline Metabolomic Profiles ofInternational journal of molecular sciences · 2025Article
- Recommendations for sample selection, collection and preparation for NMR-based metabolomics studies of blood.Metabolomics : Official journal of the Metabolomic Society · 2025Review
- Cerebrospinal fluid metabolomics of pain in patients with spinal muscle atrophy.Pain medicine (Malden, Mass.) · 2025Article
- Comprehensive, Quantitative Analysis of SRM 1950: the NIST Human Plasma Reference Material.Analytical chemistry · 2025Article
- Effects of exposure to trihalomethanes in swimming pool waters on metabolomics profile: a randomized parallel design trial.Journal of environmental health science & engineering · 2024Article
- Extraction Methods for Brain Biopsy NMR Metabolomics: Balancing Metabolite Stability and Protein Precipitation.Metabolites · 2024Article
- Evaluating protocols for reproducible targeted metabolomics by NMR.The Analyst · 2024Article
- A Reproducibility Crisis for Clinical Metabolomics Studies.Trends in analytical chemistry : TRAC · 2024Article
- Discovery of Hypoxanthine and Inosine as Robust Biomarkers for Predicting the Preanalytical Quality of Human Plasma and Serum for Metabolomics.Analytical chemistry · 2024Article
- Connecting the dots: investigating the link between environmental, genetic, and epigenetic influences in metabolomic alterations in oral squamous cell carcinoma.Journal of experimental & clinical cancer research : CR · 2024Review
- Using neural networks to obtain NMR spectra of both small and macromolecules from blood samples in a single experiment.Communications chemistry · 2024Article
- Nuclear magnetic resonance spectroscopy reveals biomarkers of stroke recovery in a mouse model of obesity-associated type 2 diabetes.Bioscience reports · 2024Article
- Applications of chromatographic methods in metabolomics: A review.Journal of chromatography. B, Analytical technologies in the biomedical and life sciences · 2024Review
- A Decrease in Branched-Chain Amino Acids after a Competitive Male Professional Volleyball Game-A Metabolomic-Based Approach.Metabolites · 2024Article
- Circulating fatty acids, genetic susceptibility and hypertension: a prospective cohort study.Frontiers in nutrition · 2024Article
52 more citing papers are in PubMed but not listed here.
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Authors and funding
2 authors at 1 institution in 1 country.
Funding
Abstract
Quantitative NMR-based metabolite profiling is challenged by the deleterious effects of abundant proteins in the intact blood plasma/serum, which underscores the need for alternative approaches. Protein removal by ultrafiltration using low molecular weight cutoff filters thus represents an important step. However, protein precipitation, an alternative and simple approach for protein removal, lacks detailed quantitative assessment for use in NMR based metabolomics. In this study, we have comprehensively evaluated the performance of protein precipitation using methanol, acetonitrile, perchloric acid, and trichloroacetic acid and ultrafiltration approaches using 1D and 2D NMR, based on the identification and absolute quantitation of 44 human blood metabolites, including a few identified for the first time in the NMR spectra of human serum. We also investigated the use of a "smart isotope tag," (15)N-cholamine for further resolution enhancement, which resulted in the detection of a number of additional metabolites. (1)H NMR of both protein precipitated and ultrafiltered serum detected all 44 metabolites with comparable reproducibility (average CV, 3.7% for precipitation; 3.6% for filtration). However, nearly half of the quantified metabolites in ultrafiltered serum exhibited 10-74% lower concentrations; specifically, tryptophan, benzoate, and 2-oxoisocaproate showed much lower concentrations compared to protein precipitated serum. These results indicate that protein precipitation using methanol offers a reliable approach for routine NMR-based metabolomics of human blood serum/plasma and should be considered as an alternative to ultrafiltration. Importantly, protein precipitation, which is commonly used by mass spectrometry (MS), promises avenues for direct comparison and correlation of metabolite data obtained from the two analytical platforms to exploit their combined strength in the metabolomics of blood.
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