scholarly journals Automated Trimethyl Sulfonium Hydroxide Derivatization Method for High-Throughput Fatty Acid Profiling by Gas Chromatography–Mass Spectrometry

Molecules ◽  
2021 ◽  
Vol 26 (20) ◽  
pp. 6246
Author(s):  
Paul Gries ◽  
Atul Singh Rathore ◽  
Xiyuan Lu ◽  
Jennifer Chiou ◽  
Yen Bao Huynh ◽  
...  

Fatty acid profiling on gas chromatography–mass spectrometry (GC–MS) platforms is typically performed offline by manually derivatizing and analyzing small batches of samples. A GC–MS system with a fully integrated robotic autosampler can significantly improve sample handling, standardize data collection, and reduce the total hands-on time required for sample analysis. In this study, we report an optimized high-throughput GC–MS-based methodology that utilizes trimethyl sulfonium hydroxide (TMSH) as a derivatization reagent to convert fatty acids into fatty acid methyl esters. An automated online derivatization method was developed, in which the robotic autosampler derivatizes each sample individually and injects it into the GC–MS system in a high-throughput manner. This study investigated the robustness of automated TMSH derivatization by comparing fatty acid standards and lipid extracts, derivatized manually in batches and online automatically from four biological matrices. Automated derivatization improved reproducibility in 19 of 33 fatty acid standards, with nearly half of the 33 confirmed fatty acids in biological samples demonstrating improved reproducibility when compared to manually derivatized samples. In summary, we show that the online TMSH-based derivatization methodology is ideal for high-throughput fatty acid analysis, allowing rapid and efficient fatty acid profiling, with reduced sample handling, faster data acquisition, and, ultimately, improved data reproducibility.

2000 ◽  
Vol 46 (2) ◽  
pp. 149-155 ◽  
Author(s):  
Patricia M Jones ◽  
Rebecca Quinn ◽  
Paul V Fennessey ◽  
Susan Tjoa ◽  
Stephen I Goodman ◽  
...  

Abstract Background: Disorders of fatty acid oxidation (FAO) are difficult to diagnose, primarily because in many of the FAO disorders measurable biochemical intermediates accumulate in body fluids only during acute illness. Increased concentrations of 3-hydroxy-fatty acids (3-OH-FAs) in the blood are indicative of FAO disorders of the long- and short-chain 3-hydroxy-acyl-CoA dehydrogenases, LCHAD and SCHAD. We describe a serum/plasma assay for the measurement of 3-OH-FAs with carbon chain lengths from C6 to C16. Methods: We used stable isotope dilution gas chromatography-mass spectrometry (GC-MS) with electron impact ionization and selected ion monitoring. Natural and isotope-labeled compounds were synthesized for the assay. Results: The assay was linear from 0.2 to 50 μmol/L for all six 3-OH-FAs. CVs were 5–15% at concentrations near the upper limits seen in healthy subjects. In 43 subjects, the medians (and ranges) in μmol/L were as follows: 3-OH-C6, 0.8 (0.3–2.2); 3-OH-C8, 0.4 (0.2–1.0); 3-OH-C10, 0.3 (0.2–0.6); 3-OH-C12, 0.3 (0.2–0.6); 3-OH-C14, 0.2 (0.0–0.4); and 3-OH-C16, 0.2 (0.0–0.5). 3-OH-FAs were increased in infants receiving formula containing medium chain triglycerides. Two patients diagnosed with LCHAD deficiency showed marked increases in 3-OH-C14 and 3-OH-C16 concentrations. Two patients diagnosed with SCHAD deficiency showed increased shorter chain 3-OH-FAs but no increases in 3-OH-C14 to 3-OH-C16. Conclusion: Measuring blood concentrations of the 3-OH-FAs with this assay may be a valuable tool for helping to rapidly identify deficiencies in LCHAD and SCHAD and may also provide useful information about the status of the FAO pathway.


2019 ◽  
Vol 2019 ◽  
pp. 1-11
Author(s):  
Kwang Seo Park ◽  
Yun Ju Kim ◽  
Eun Kyung Choe

To implement EU REACH- (Registration, Evaluation, and Authorization of Chemicals-) like chemical legislations in various countries of which the purpose is human and environment safety, the first step is substance identification followed by the hazard and risk assessments. Although both structural and composition identifications are required, the latter can more importantly result in the essential data to fill out the required substance information such as purity and concentrations of constituents, as well as impurities. With fatty acid zinc salts (FAZSs) as an exemplary industrial chemical of which chromatographic and nuclear magnetic resonance (NMR) analyses were impossible due to their insolubility in water and any organic solvents, the composition characterization was tried by preparing their fatty acid methyl esters (FAMEs) using the conc. HCl/methanol/toluene method. This acid-catalyzed methyl esterification was optimized with zinc stearate as a surrogate substance. Gas chromatography-mass spectrometry (GC-MS) and NMR analyses on methyl-esterified products revealed that the optimum conditions were at 90°C for 10 min or 45°C for 30 min with two equivalent HCl as well as at 45°C for 10 min with five equivalent HCl. Almost all zinc stearates were converted into the corresponding fatty acids with 97–99% conversion rates. Free fatty acids (FFAs) were detected in extracted ion chromatograms of pyrolysis-gas chromatography-mass spectrometry (Py-GC-MS) in the methyl-esterified products with incomplete conversions of 73∼79%. The optimized conc. HCl/methanol/toluene method of direct one-step reaction from FAZSs was compared with the two-step NaOH saponification/BF3-methanol method after acidic hydrolysis of FAZSs. The mechanism of fatty acid zinc salts into free fatty acids and fatty acid methyl esters was suggested with the evidence of the formation of Zn(OH)2.


2015 ◽  
Vol 451 ◽  
pp. 183-190 ◽  
Author(s):  
Huai-Hsuan Chiu ◽  
Sung-Jeng Tsai ◽  
Y. Jane Tseng ◽  
Ming-Shiang Wu ◽  
Wei-Chih Liao ◽  
...  

2021 ◽  
Vol 10 (1) ◽  
Author(s):  
Jessica E. Ollinik ◽  
Candice C. Chua ◽  
Pamela Brunswick ◽  
Robert W. Elner ◽  
Oxana Blajkevitch ◽  
...  

AbstractBiofilm communities on intertidal mudflats are recognized as major producers of nutrients, especially fatty acids. The rising threats posed by both climatic and anthropogenic stressors increase the necessity of understanding and conserving these communities. Shorebirds provide a proxy for studying the complex ecology of biofilm communities because of their heavy reliance on fatty acids from diatomaceous biofilm for successful long-distance migration. Herein, we review biofilm feeding patterns by migratory shorebirds, experimental design considerations for sampling and studying the fatty acid content of biofilm, and the literature describing established and emerging analytical methodology. Techniques for fatty acid analysis include the commonly employed gas chromatography–flame ionization detection (GC/FID) and gas chromatography–mass spectrometry (GC/MS) with derivatization. Liquid chromatography–mass spectrometry (LC/MS) and liquid chromatography–quadrupole time of flight (LC/QTOF) are newly emerging techniques that enable derivatization to be eliminated. In addition, Fourier transform infrared spectroscopy (FT/IR), a common instrument in chemistry laboratories, has applications in fatty acid research, specifically for screening. Using a combination of sampling and analytical methods is necessary for improved understanding of intertidal biofilm, both as a source of essential fatty acids in aquatic systems and a critical food for shorebirds.


Sign in / Sign up

Export Citation Format

Share Document