Detection of Lipids and Proteins on Biological Surfaces using Imaging Mass Spectrometry
Doctoral thesis, 2016

Time-of-flight secondary ion mass spectrometry (ToF-SIMS) is a technique that can be used for imaging the spatial distribution of many different molecules at the same time. It is very sensitive for detection of small biomolecules, such as lipids, whereas larger biomolecules, such as peptides and proteins, cannot be detected as intact entities due to fragmentation. In this work, we have explored an alternative approach for detection of peptides and proteins with ToF-SIMS, using liposomes for labeling the target of interest. In this way, both lipids and proteins can be imaged at the same time, which opens up for the opportunity to investigate lipid-protein interactions. The method has been applied for detection of biomolecules on two different biological surfaces; (1) a model surface containing controlled concentrations of target biomolecules bound to the substrate and (2) brain tissue sections from Alzheimer’s disease transgenic mice. Other techniques, such as fluorescence microscopy and quartz crystal microbalance with dissipation monitoring (QCM-D), have also been used for the characterization of liposomes binding to the surface. Another imaging mass spectrometry technique, matrix-assisted laser desorption/ionization (MALDI), was also employed on mouse brain tissue sections for detection and investigation of amyloid-β deposits, a peptide associated with Alzheimer’s disease. This thesis thus shows how different techniques can be combined for investigation of biomolecules on complex biological surfaces, in order to potentially provide new information about the mechanism of neurodegeneration in Alzheimer’s disease.






Imaging Mass Spectrometry

Alzheimer’s disease




Opponent: Mary Kraft


Louise M Carlred

Chalmers, Physics, Biological Physics

Denna avhandling syftar till att ta fram metoder för att kunna detektera och studera lipider och proteiner närmare. Genom att använda avbildande masspektrometri kan man detektera och lokalisera en mängd olika molekyler, såsom olika typer av lipider, på biologiska ytor. För att utveckla denna metod för att även kunna detektera specifika proteiner på ytan har vi producerat liposomer, vilket är små partiklar som omges av ett hölje av lipider, som binder specifikt till proteinerna. Med hjälp av dessa liposomer har vi lyckats avbilda Amyloid-β, en peptide involverad i Alzheimer's sjukdom, parallellt med ett flertal olika lipider i mushjärnor med Alzheimers. Denna metod kan därför användas för att studera det molekylära samspelet närmare, vilket skulle kunna leda till ökade insikter kring mekanismen bakom Alzheimers sjukdom.

Imaging mass spectrometry is a technique that can be used for detection of biological molecules, such as lipids and proteins, on surfaces. However, most methods cannot detect the lipids and proteins at the same time. In this thesis we have therefore developed a method for targeting the molecule of interest using liposomes. In this way, it was possible to image the distribution of Amyloid-beta, a peptide relevant to Alzheimer's disease, i parallel with several lipids in Alzheimer's disease mouse brains. Furthermore, it was also possible to detect several targets, in particular the vitamin biotin and the glycosphingolipid GM1, at the same time in supported lipid bilayers. Thus, this method opens up for new possibilities to investigate the interactions between lipids and proteins, that potentially could provide new information about the mechanism behind Alzheimer's disease.

Subject Categories

Biochemistry and Molecular Biology

Analytical Chemistry



Areas of Advance

Life Science Engineering (2010-2018)



Doktorsavhandlingar vid Chalmers tekniska högskola. Ny serie: 4078


Opponent: Mary Kraft

More information