A simple and precise method for measurement of serum free carnitine and acylcarnitines by isotope dilution HILIC-ESI-MS/MS

• Published in: International journal of mass spectrometry Vol. 446; p. 116208
• Main Authors: Wang, Mo, Yang, Ruiyue, Mu, Hongna, Zeng, Jie, Zhang, Tianjiao, Zhou, Weiyan, Wang, Siming, Tang, Yueming, Li, Hongxia, Zhang, Chuanbao, Chen, Wenxiang, Dong, Jun
• Format: Journal Article
• Language: English
• Published: Elsevier B.V 01.12.2019
• Subjects: Acylcarnitine; Carnitine; Coronary atherosclerotic artery disease; Liquid chromatography tandem mass spectrometry; LDL-C; AcyCNs; Acylcarnitine; MRM; FBG; C0; C2; HDL-C; C3; LC-MS/MS; C5; DBP; C6; C8; ESI; HILIC; C10:1; Liquid chromatography tandem mass spectrometry; SBP; C10; C12; C18:1; CAD; C14; C16; C18; Carnitine; TC; TG; hsCRP; Coronary atherosclerotic artery disease
• ISSN: 1387-3806; 1873-2798
• DOI: 10.1016/j.ijms.2019.116208

Recent studies have found that carnitine and acylcarnitines (AcyCNs) are potential biomarkers for many metabolic diseases, including inherited disorders, diabetes and coronary atherosclerotic artery disease (CAD). Here we presented and validated a method for measurement of free carnitine and twelve AcyCNs in human serum by using electrospray ionization tandem mass spectrometry (ESI-MS/MS). Serum samples were mixed with isotopic labeled internal standards and extracted with isopropanol. Carnitine and AcyCNs were separated within 5min by isocratic elution on a hydrophilic interaction liquid chromatographic column (HILIC) and detected with electrospray ionization (ESI) in positive ion mode with multiple reaction monitor (MRM) mode. This method was linear in response with correlation coefficients higher than 0.999. Analytical recoveries were 89.4%–105.4% with an average of 98.7%. The intra-run and total imprecisions were 0.9–4.7% and 1.5–14.1%, respectively. Stability tests showed that all the compounds were stable in serum for at least 6 month at −80 °C, but unstable when stored at room temperature (RM) and 4 °C.Serum carnitine and AcyCNs concentrations of 472 apparently healthy subjects were analyzed. Significant associations between the metabolites and traditional CAD risk factors were observed. The established HILIC–ESI-MS/MS method was simple, precise, and sensitive and may be used as an efficient tool in CAD risk assessment and research. [Display omitted] •A precise HILIC-ESI-MS/MS method for simultaneous quantification of serum thirteen acylcarnitines was developed.•The 13 metabolites were effectively separated within 5 min.•472 volunteers were analyzed.•Significant associations between the metabolites and classic CVD risk factors were observed.•This method is simple and precise and is suitable for CVD risk assessment.