Laser-Induced In-Source Decay Applied to the Determination of Amyloid-Beta in Alzheimer's Brains

Andrea R. Kelley*, George Perry, Rudolph J. Castellani, Stephan B.H. Bach

*Corresponding author for this work

Research output: Contribution to journalArticlepeer-review

22 Scopus citations


A method for the analysis of amyloid-beta peptides in isolated plaques and intact tissue sections affected by Alzheimer's disease (AD) is presented. This method employs matrix-assisted laser desorption/ionization (MALDI) time-of-flight mass spectrometry and the inherent laser-induced in-source decay (ISD) that occurs coupled with imaging mass spectrometry (IMS) to investigate the composition of these samples eliminating the need for other confirmational MS/MS techniques. These results demonstrate this technique's usefulness for the identification of amyloid-beta peptides in tissue and isolated senile plaques from AD patients using the reproducible fragmentation pattern demonstrated via the laser-induced ISD of synthetic amyloid-beta peptide clips (1-40, 1-42). Clear differences between the hippocampal AD tissue and the control hippocampal tissue regarding the presence of amyloid-beta have been identified. These are based on laser-induced ISD of standard amyloid-beta clips as controls as well as the analysis of isolated senile plaques as a confirmation before tissue analysis. Using the resulting observed peptide clip masses from the control data, we present mass spectrometry based identification of the amyloid-beta peptides in both isolated plaques and hippocampal regions of those patients diagnosed with AD.

Original languageEnglish (US)
Pages (from-to)261-268
Number of pages8
JournalACS Chemical Neuroscience
Issue number3
StatePublished - Mar 16 2016


  • Alzheimer's disease
  • amyloid-beta
  • imaging
  • mass spectrometry

ASJC Scopus subject areas

  • Cognitive Neuroscience
  • Biochemistry
  • Physiology
  • Cell Biology


Dive into the research topics of 'Laser-Induced In-Source Decay Applied to the Determination of Amyloid-Beta in Alzheimer's Brains'. Together they form a unique fingerprint.

Cite this