Determination of carbon isotope ratios for honey samples by means of a liquid chromatography/isotope ratio mass spectrometry system coupled with a post‐column pump

Abstract

The column flow rate could be arbitrarily adjusted with the post-column pump. We applied the improved method to 26 commercial honey samples. Our results can be expected to be useful for other researchers who use LC/IRMS.

Online wet oxidation/isotope ratio mass spectrometry method for determination of stable carbon isotope ratios of water‐soluble organic carbon in particulate matter

“…Therefore, we concluded that the limits of detection (precision <±0.3‰ and accuracy <±0.3‰) for levoglucosan and oxalic acid were 1111 and 1133 ngC, respectively. These values are consistent with previously reported values for glucose and fructose (800 ngC) . The oxidation method has an accuracy within 1.2‰ and a precision within 0.98‰ and needs several μgC of sample (values read from figure) to perform IRMS analysis with a GasBench system .…”

“…Regression analysis of the correlation between EA/IRMS and wet oxidation/IRMS data for five reagents ( d ‐mannitol, mannosan, galactosan, malonic acid, and succinic acid) gave a slope of 1.03, an intercept of 0.11, and a high correlation coefficient (>0.99, Figure A). In a previous study, a slope of 0.99 and a correlation coefficient of 0.98 were obtained upon analysis of eight sugar reagents by EA/IRMS with a LiquiFace interface . In another study, analysis of 12 compounds (alcohols, carbohydrates, and organic acids) resulted in a slope close to unity and a high correlation coefficient (>0.99) .…”

“…The δ 13 C values of WSOC were measured by means of wet oxidation/IRMS at Akita Prefectural University (Akita, Japan). The wet oxidation/IRMS system has been described previously . Briefly, the LC system (Shimadzu Co., Kyoto, Japan) was coupled to an IRMS instrument (Isoprime, Elementar UK, Manchester, UK) via a LiquiFace interface (Elementar).…”

“…The wet oxidation/ IRMS system has been described previously. 34 Stable carbon isotope ratios, expressed in δ notation in permil (‰) units, were calculated as follows:…”

“…The relationships between the measured δ 13 These values are consistent with previously reported values for glucose and fructose (800 ngC). 34 The oxidation method has an accuracy within 1.2‰ and a precision within 0.98‰ and needs several μgC of sample (values read from figure) to perform IRMS analysis with a GasBench system. 17 The limit of detection for the combustion method is not known.…”