Immuno‐Desorption Electrospray Ionization Mass Spectrometry Imaging Identifies Functional Macromolecules by Using Microdroplet‐Cleavable Mass Tags

Abstract

We present immunoassay‐based desorption electrospray ionization mass spectrometry imaging (immuno‐DESI‐MSI) to visualize functional macromolecules such as drug targets and cascade signaling factors. A set of boronic acid mass tags (BMTs) were synthesized to label antibodies as MSI probes. The boronic ester bond is employed to cross‐link the BMT with the galactosamine‐modified antibody. The BMT can be released from its tethered antibody by ultrafast cleavage of the boronic ester bond caused by the acidic condition of sprayed DESI microdroplets containing water. The fluorescent moiety enables the BMT to work in both optical and MS imaging modes. The positively charged quaternary ammonium group enhances the ionization efficiency. The introduction of the boron element also makes mass tags readily identified because of its unique isotope pattern. Immuno‐DESI‐MSI provides an appealing strategy to spatially map macromolecules beyond what can be observed by conventional DESI‐MSI, provided antibodies are available to the targeted molecules of interest.

Document Details

Document Type
Pub Defense Publication
Publication Date
Jan 24, 2023
Source ID
10.1002/anie.202216969

Entities

People

  • Chao Li
  • Qingce Zang
  • Richard Zare
  • Tianhao Zhou
  • Xiaowei Song

Organizations

  • Air Force Office of Scientific Research
  • Fudan University
  • National Natural Science Foundation of China
  • Peking Union Medical College
  • Stanford University
  • Tianjin Medical University

Tags

Fields of Study

  • Chemistry

Readers

  • Analytical Chemistry
  • Molecular and Cellular Biochemistry