Mirjana Radovanovic, Graham Jones, Richard O Day, Peter Galettis, Ross L G Norris
{"title":"减轻定量液相色谱-串联质谱法中分析物与稳定同位素标记内标交叉信号的影响。","authors":"Mirjana Radovanovic, Graham Jones, Richard O Day, Peter Galettis, Ross L G Norris","doi":"10.1016/j.jmsacl.2022.04.002","DOIUrl":null,"url":null,"abstract":"<p><strong>Background: </strong>Utilising stable isotope labelled internal standards (SIL-IS) in quantitative LC-MS/MS drug analysis is the most widely used approach to normalise for variability during sample quantification processes. However, compounds containing atoms such as Sulphur, Chlorine or Bromine, could potentially cause cross-signal contribution to the SIL-IS from the naturally occurring isotopes, resulting in non-linear calibration curves. A simple, novel method of mitigating the effect is presented here. It entails monitoring of a less abundant SIL-IS isotope, as the precursor ion, of a mass that has no/minimal isotopic contribution from the analyte isotopes.</p><p><strong>Methods: </strong>Experiments were conducted on two LC-MS/MS analysers: Waters Xevo TQ-S and Shimadzu 8050. Flucloxacillin (FLX) was used as an example. Two transitions were selected for FLX (<i>m</i>/<i>z</i> 454 → 160 → 295) and one for each of the SIL-IS isotopes (<i>m</i>/<i>z</i> 458 → 160 for the isotope 457 g/mol and <i>m</i>/<i>z</i> 460 → 160 for the isotope 459 g/mol). Assay biases were assessed at three SIL-IS concentrations: 0.7, 7 and 14 mg/L for each isotope.</p><p><strong>Results: </strong>When using the SIL-IS isotope <i>m</i>/<i>z</i> 458 → 160 at a concentration of 0.7 mg/L, biases were up to 36.9 % on both instruments. Increasing the SIL-IS concentration to 14 mg/L, reduced the bias to 5.8 %. Using the less abundant isotope, <i>m</i>/<i>z</i> 460 → 160, resulted in biases of 13.9 % at an SIL-IS concentration of 0.7 mg/L.</p><p><strong>Conclusions: </strong>Applying this method will mitigate cross-signal contribution from the analyte isotopes to the corresponding SIL-IS, minimise the use of SIL-IS, and, thereby, reduce overall cost.</p>","PeriodicalId":52406,"journal":{"name":"Journal of Mass Spectrometry and Advances in the Clinical Lab","volume":null,"pages":null},"PeriodicalIF":3.1000,"publicationDate":"2022-04-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC9065310/pdf/","citationCount":"0","resultStr":"{\"title\":\"Mitigating analyte to stable isotope labelled internal standard cross-signal contribution in quantitative liquid chromatography-tandem mass spectrometry.\",\"authors\":\"Mirjana Radovanovic, Graham Jones, Richard O Day, Peter Galettis, Ross L G Norris\",\"doi\":\"10.1016/j.jmsacl.2022.04.002\",\"DOIUrl\":null,\"url\":null,\"abstract\":\"<p><strong>Background: </strong>Utilising stable isotope labelled internal standards (SIL-IS) in quantitative LC-MS/MS drug analysis is the most widely used approach to normalise for variability during sample quantification processes. However, compounds containing atoms such as Sulphur, Chlorine or Bromine, could potentially cause cross-signal contribution to the SIL-IS from the naturally occurring isotopes, resulting in non-linear calibration curves. A simple, novel method of mitigating the effect is presented here. It entails monitoring of a less abundant SIL-IS isotope, as the precursor ion, of a mass that has no/minimal isotopic contribution from the analyte isotopes.</p><p><strong>Methods: </strong>Experiments were conducted on two LC-MS/MS analysers: Waters Xevo TQ-S and Shimadzu 8050. Flucloxacillin (FLX) was used as an example. Two transitions were selected for FLX (<i>m</i>/<i>z</i> 454 → 160 → 295) and one for each of the SIL-IS isotopes (<i>m</i>/<i>z</i> 458 → 160 for the isotope 457 g/mol and <i>m</i>/<i>z</i> 460 → 160 for the isotope 459 g/mol). Assay biases were assessed at three SIL-IS concentrations: 0.7, 7 and 14 mg/L for each isotope.</p><p><strong>Results: </strong>When using the SIL-IS isotope <i>m</i>/<i>z</i> 458 → 160 at a concentration of 0.7 mg/L, biases were up to 36.9 % on both instruments. Increasing the SIL-IS concentration to 14 mg/L, reduced the bias to 5.8 %. Using the less abundant isotope, <i>m</i>/<i>z</i> 460 → 160, resulted in biases of 13.9 % at an SIL-IS concentration of 0.7 mg/L.</p><p><strong>Conclusions: </strong>Applying this method will mitigate cross-signal contribution from the analyte isotopes to the corresponding SIL-IS, minimise the use of SIL-IS, and, thereby, reduce overall cost.</p>\",\"PeriodicalId\":52406,\"journal\":{\"name\":\"Journal of Mass Spectrometry and Advances in the Clinical Lab\",\"volume\":null,\"pages\":null},\"PeriodicalIF\":3.1000,\"publicationDate\":\"2022-04-26\",\"publicationTypes\":\"Journal Article\",\"fieldsOfStudy\":null,\"isOpenAccess\":false,\"openAccessPdf\":\"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC9065310/pdf/\",\"citationCount\":\"0\",\"resultStr\":null,\"platform\":\"Semanticscholar\",\"paperid\":null,\"PeriodicalName\":\"Journal of Mass Spectrometry and Advances in the Clinical Lab\",\"FirstCategoryId\":\"3\",\"ListUrlMain\":\"https://doi.org/10.1016/j.jmsacl.2022.04.002\",\"RegionNum\":4,\"RegionCategory\":\"医学\",\"ArticlePicture\":[],\"TitleCN\":null,\"AbstractTextCN\":null,\"PMCID\":null,\"EPubDate\":\"2022/4/1 0:00:00\",\"PubModel\":\"eCollection\",\"JCR\":\"Q2\",\"JCRName\":\"MEDICAL LABORATORY TECHNOLOGY\",\"Score\":null,\"Total\":0}","platform":"Semanticscholar","paperid":null,"PeriodicalName":"Journal of Mass Spectrometry and Advances in the Clinical Lab","FirstCategoryId":"3","ListUrlMain":"https://doi.org/10.1016/j.jmsacl.2022.04.002","RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"2022/4/1 0:00:00","PubModel":"eCollection","JCR":"Q2","JCRName":"MEDICAL LABORATORY TECHNOLOGY","Score":null,"Total":0}
Mitigating analyte to stable isotope labelled internal standard cross-signal contribution in quantitative liquid chromatography-tandem mass spectrometry.
Background: Utilising stable isotope labelled internal standards (SIL-IS) in quantitative LC-MS/MS drug analysis is the most widely used approach to normalise for variability during sample quantification processes. However, compounds containing atoms such as Sulphur, Chlorine or Bromine, could potentially cause cross-signal contribution to the SIL-IS from the naturally occurring isotopes, resulting in non-linear calibration curves. A simple, novel method of mitigating the effect is presented here. It entails monitoring of a less abundant SIL-IS isotope, as the precursor ion, of a mass that has no/minimal isotopic contribution from the analyte isotopes.
Methods: Experiments were conducted on two LC-MS/MS analysers: Waters Xevo TQ-S and Shimadzu 8050. Flucloxacillin (FLX) was used as an example. Two transitions were selected for FLX (m/z 454 → 160 → 295) and one for each of the SIL-IS isotopes (m/z 458 → 160 for the isotope 457 g/mol and m/z 460 → 160 for the isotope 459 g/mol). Assay biases were assessed at three SIL-IS concentrations: 0.7, 7 and 14 mg/L for each isotope.
Results: When using the SIL-IS isotope m/z 458 → 160 at a concentration of 0.7 mg/L, biases were up to 36.9 % on both instruments. Increasing the SIL-IS concentration to 14 mg/L, reduced the bias to 5.8 %. Using the less abundant isotope, m/z 460 → 160, resulted in biases of 13.9 % at an SIL-IS concentration of 0.7 mg/L.
Conclusions: Applying this method will mitigate cross-signal contribution from the analyte isotopes to the corresponding SIL-IS, minimise the use of SIL-IS, and, thereby, reduce overall cost.