Measurement of homoarginine in human and mouse plasma by LC-MS/MS and ELISA: a comparison and a biological application
Standard
Measurement of homoarginine in human and mouse plasma by LC-MS/MS and ELISA: a comparison and a biological application. / Cordts, Kathrin; Atzler, Dorothee; Qaderi, Vazhma; Sydow, Karsten; Böger, Rainer H; Choe, Chi-Un; Schwedhelm, Edzard.
In: AMINO ACIDS, Vol. 47, No. 9, 09.2015, p. 2015-22.Research output: SCORING: Contribution to journal › SCORING: Journal article › Research › peer-review
Harvard
APA
Vancouver
Bibtex
}
RIS
TY - JOUR
T1 - Measurement of homoarginine in human and mouse plasma by LC-MS/MS and ELISA: a comparison and a biological application
AU - Cordts, Kathrin
AU - Atzler, Dorothee
AU - Qaderi, Vazhma
AU - Sydow, Karsten
AU - Böger, Rainer H
AU - Choe, Chi-Un
AU - Schwedhelm, Edzard
PY - 2015/9
Y1 - 2015/9
N2 - Homoarginine (hArg) is a non-essential amino acid that was identified as a risk marker for cardiovascular disease. Several analytical methods have been described for the quantification of hArg in biological samples. The aim of this study was to compare a liquid chromatography-tandem mass spectrometric (LC-MS/MS) approach with a commercially available enzyme-linked immunosorbent assay (ELISA). Determination of hArg concentrations in ELISA calibration standards measured by both methods revealed a correlation coefficient r (2) of 0.99, for LC-MS/MS calibrators r (2) was 0.997. However, linear regression analysis between the two assays for hArg concentrations in human plasma samples revealed a correlation coefficient r (2) of 0.78. Plasma concentrations obtained from LC-MS/MS are on average 29 % higher than those by ELISA. We investigated the hArg-isobaric N (ε)-trimethyllysine as potential source for the higher observed values, but evaluation of mass spectra indicated that N (ε)-trimethyllysine did not interfere with hArg quantification in our LC-MS/MS method. Both quantification methods were applied to measure hArg in (1) a case-control study of acute coronary syndrome and (2) L-arginine:glycine amidinotransferase-deficient mice. Our LC-MS/MS and the commercially available ELISA assay are suitable for hArg measurement in human and mouse plasma, but different reference values for each method need to be considered.
AB - Homoarginine (hArg) is a non-essential amino acid that was identified as a risk marker for cardiovascular disease. Several analytical methods have been described for the quantification of hArg in biological samples. The aim of this study was to compare a liquid chromatography-tandem mass spectrometric (LC-MS/MS) approach with a commercially available enzyme-linked immunosorbent assay (ELISA). Determination of hArg concentrations in ELISA calibration standards measured by both methods revealed a correlation coefficient r (2) of 0.99, for LC-MS/MS calibrators r (2) was 0.997. However, linear regression analysis between the two assays for hArg concentrations in human plasma samples revealed a correlation coefficient r (2) of 0.78. Plasma concentrations obtained from LC-MS/MS are on average 29 % higher than those by ELISA. We investigated the hArg-isobaric N (ε)-trimethyllysine as potential source for the higher observed values, but evaluation of mass spectra indicated that N (ε)-trimethyllysine did not interfere with hArg quantification in our LC-MS/MS method. Both quantification methods were applied to measure hArg in (1) a case-control study of acute coronary syndrome and (2) L-arginine:glycine amidinotransferase-deficient mice. Our LC-MS/MS and the commercially available ELISA assay are suitable for hArg measurement in human and mouse plasma, but different reference values for each method need to be considered.
U2 - 10.1007/s00726-015-2037-7
DO - 10.1007/s00726-015-2037-7
M3 - SCORING: Journal article
C2 - 26159673
VL - 47
SP - 2015
EP - 2022
JO - AMINO ACIDS
JF - AMINO ACIDS
SN - 0939-4451
IS - 9
ER -
