High-resolution LC-MS/MS solution for improved quantification of peptides in a complex matrix


Featuring the ZenoTOF 7600 LC-MS/MS system

Shane Needham1 , Eshani Nandita2 , Lei Xiong, Elliott Jones2 , Zoe Zhang2 , Kerstin Pohl2
1Alturas Analytics Inc, Moscow, Idaho; 2SCIEX, USA

Abstract


Improved selectivity and greater sensitivity were achieved for peptide quantitfication in a complex matrix using the ZenoTOF 7600 system featuring the Zeno trap. The greater mass resolution provides selectivity between target peptide versus matrix-derived interferences and general high background effects. This enhanced selectivity aids in superior quantitative results in terms of LOQ, precise data integration, improved reproducibility, and linear dynamic range. In addition, enhanced sensitivity for peptide quantification was achievable using the Zeno trap to improve the duty cycle versus traditional time-of-flight systems.

Traditional workflows for quantitative bioanalyses, such as immunological assays, have been displaced by LC-MS/MS analysis on a triple quadrupole mass spectrometer. Immunoassays often lack selectivity, specificity, and have a limited linear dynamic range. While the triple quadrupole platform provides excellent sensitivity and quantitative performance, there can be some limitations with background interference based on the lower resolution considering the type of mass analyzer. Background interference is a common issue for workflows where analytes are present in a highly complex matrix. High-resolution accurate mass spectrometry (HRAMS) has been increasingly adopted for quantitative bioanalysis.1,2 The ZenoTOF 7600 system offers an exceptional combination of mass resolution, sensitivity, and acquisition speed for quantitative analysis. It also aids in more accurate and automated integration, the potential for less ion path tuning, the ability to change measured fragments post-acquisition, and improved reproducibility and LDR when interferences are mitigated. These attributes complement the excellent sensitivity of a nominal mass triple quadrupole system such as the SCIEX Triple Quad 7500 LCMS/MS system − QTRAP Ready or SCIEX Triple Quad 6500+ LC-MS/MS system for a biopharmaceutical lab which requires a full range of capabilities.

The ZenoTOF 7600 system offers a high-resolution MS/MSbased acquisition mode for peptide quantification with Zeno MRMHR, along with improved sensitivity using the Zeno trap. The implementation of the Zeno trap allows for improvement of the duty cycle by ≥90 %, thereby improving overall MS/MS sensitivity.

Key features of the ZenoTOF 7600 system for peptide quantification
 

  • Gain higher sensitivity for peptide quantification using the Zeno trap, by enhancing duty cycle through an accumulation of ions during each TOF pulse

  • Achieve greater selectivity between target peptides and matrix-related components with the higher mass resolution offered by the ZenoTOF 7600 system

  • Ensure exceptional accuracy and precision for quantitative workflows using the ZenoTOF 7600 system

  • Achieve superior sensitivity for peptide quantification using HRAMS MS/MS in comparison with single MS mode

  • Perform highly automated and accurate peak integration given the improvements in selectivity with higher resolution and ensure overall data integrity

  • Easily acquire, process, and manage data on a single platform using the SCIEX OS software 

Figure 1. ZenoTOF 7600 system offers greater selectivity for peptide quantification compared with a triple quadrupole system. XIC of the matrix blank from the triple quadrupole system shows significant matrix interference at retention time of analyte resulting in poor quantitative performance. Overall, the ZenoTOF 7600 system reduces time for method development and optimization.