Quantitative Determination of Total L-Carnitine in Infant Formula, Follow-up Formula, and Raw Materials by Liquid Chromatography with Tandem Mass Spectrometry

Nadaoka, Isao; Hatakeyama, Emi; Tanada, Chihiro; Sakamoto, Tasuku; Fukaya, Shinichi; Akiba, Takashi; Inoue, Kōichi; Yamano, Yutaka; Toyo’oka, Toshimasa

doi:10.2116/analsci.30.839

Cited by 10 publications

(11 citation statements)

References 27 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Furthermore, each ion peak can be separately detected because the stable isotope‐labeled peak has an increased molecular weight from the native form. This normalization method has been used for a large number of quantitative analyses of targeted metabolites in many fields (Inoue et al, ; Nadaoka et al, ; Zheng et al, ).…”

Section: Internal Standard Normalizationmentioning

confidence: 99%

The great importance of normalization of LC–MS data for highly‐accurate non‐targeted metabolomics

Mizuno

Ueda

Kobayashi

et al. 2016

Biomedical Chromatography

View full text Add to dashboard Cite

The non-targeted metabolomics analysis of biological samples is very important to understand biological functions and diseases. LC combined with electrospray ionization-based MS has been a powerful tool and widely used for metabolomic analyses. However, the ionization efficiency of electrospray ionization fluctuates for various unexpected reasons such as matrix effects and intraday variations of the instrument performances. To remove these fluctuations, normalization methods have been developed. Such techniques include increasing the sensitivity, separating coeluting components and normalizing the ionization efficiencies. Normalization techniques allow simultaneously correcting of the ionization efficiencies of the detected metabolite peaks and achieving quantitative non-targeted metabolomics. In this review paper, we focused on these normalization methods for non-targeted metabolomics by LC-MS.

show abstract

Section: Internal Standard Normalizationmentioning

confidence: 99%

The great importance of normalization of LC–MS data for highly‐accurate non‐targeted metabolomics

Mizuno

Ueda

Kobayashi

et al. 2016

Biomedical Chromatography

View full text Add to dashboard Cite

show abstract

“…As shown in Supporting Information Table S4, the values for free and total l‐ carnitine were similar in all samples, which might be related to different milk sources. Concentrations of conjugated l‐ carnitine ranged from 5.3 to 11.4 mg/100 g, which is the total acetyl‐ l ‐carnitine in infant formula.…”

Section: Resultsmentioning

confidence: 99%

“…Various hydrolysis methods have been reported. When using basic saponification , excess base must be neutralized to enhance the response of analytes in electrospray positive‐ion mode, but the MS/MS signal is reduced by the resulting salts. Acid hydrolysis is simple, timesaving, and salt‐free because neutralization is not required.…”

Section: Introductionmentioning

confidence: 99%

Simultaneous determination of free and total choline and l‐carnitine in infant formula using hydrophilic interaction liquid chromatography with tandem mass spectrometry

Zheng

Xia

et al. 2018

J of Separation Science

View full text Add to dashboard Cite

A quick, simple, and reliable method was developed for the simultaneous determination of free and total choline and l-carnitine in infant formula employing a novel hydrophilic interaction liquid chromatography with tandem mass spectrometry method. Microwave-assisted hydrolysis was used to shorten the hydrolysis time to only 15 min. A novel Click XIon zwitterionic stationary phase was chosen because it gave better retention, perfect resolution, and sharper symmetrical peaks compared to traditional columns. The matrix effect under different experimental conditions was evaluated by using the matrix effect factor, which employs stable isotopically labeled internal standards and is more appropriate for evaluating the matrix effect related to endogenous analytes. The accuracy and precision of the method were validated with certified reference materials. The fortified recovery values for choline and l-carnitine were between 85.0 and 104% with relevant standard deviations <5.0%. The established method was applied to the analysis of real infant formulas, demonstrating its applicability and feasibility.

show abstract

“…In spite of for many laboratories around the world radioenzymatic assay is still a useful method for free and total carnitine measurement 12,13 , tandem mass spectrometry constitutes the more precise technique for this kind of sizes; however, when total carnitine is measured by tandem mass spectrometry, total carnitine is measured after alkaline hydrolysis of acylcarnitines 14 . Plasma samples are neutralized by the addition of hydrochloric acid and then buffered before the analysis by tandem mass spectrometry, but these steps spend more chemicals and are time-consuming 15 .…”

Section: Introductionmentioning

confidence: 99%

Untitled

Osório¹,

Castañeda²

2018

Duazary

View full text Add to dashboard Cite

The present study establishes whether the pH of samples is crucial for measuring total carnitine in human plasma by tandem mass spectrometry and if it is necessary to neutralize the samples after alkaline hydrolysis of acylcarnitines. Free and total carnitine of ten plasma samples were measured by a radioenzymatic assay as a reference method, and forward there were analyzed by tandem mass spectrometry divided into two groups: treated with hydrochloric acid and without hydrochloric acid measuring each sample five times for both variables. Free and total carnitine concentrations were similar for the radioenzymatic essay and tandem mass spectrometry. There was no significant difference between the two analyzed variables (treated with hydrochloric acid and without hydrochloric acid). It could be concluded that the pH of samples is no crucial for measuring total carnitine in plasma by tandem mass spectrometry, and it is not necessary to neutralize the samples after alkaline hydrolysis of acylcarnitines, then the shorter method, without adding hydrochloric acid can be used for total carnitine measurement in plasma by tandem mass spectrometry

show abstract

Quantitative Determination of Total L-Carnitine in Infant Formula, Follow-up Formula, and Raw Materials by Liquid Chromatography with Tandem Mass Spectrometry

Cited by 10 publications

References 27 publications

The great importance of normalization of LC–MS data for highly‐accurate non‐targeted metabolomics

The great importance of normalization of LC–MS data for highly‐accurate non‐targeted metabolomics

Simultaneous determination of free and total choline and l‐carnitine in infant formula using hydrophilic interaction liquid chromatography with tandem mass spectrometry

Untitled

Contact Info

Product

Resources

About