PMID- 29544258
OWN - NLM
STAT- MEDLINE
DCOM- 20190225
LR  - 20190225
IS  - 1559-4106 (Electronic)
IS  - 1559-4106 (Linking)
VI  - 13
IP  - 3
DP  - 2018 Mar 15
TI  - Toward multiplexed quantification of biomolecules on surfaces using 
      time-of-flight secondary ion mass spectrometry.
PG  - 03B413
LID - 10.1116/1.5019749 [doi]
AB  - Accurate detection and quantification of individual molecules is important for 
      the development of improved diagnostic methods as well as biochemical 
      characterization of disease progression and treatments. Time-of-flight secondary 
      ion mass spectrometry (ToF-SIMS) is a surface analysis technique capable of 
      imaging the distribution of specific molecules on surfaces with a high spatial 
      resolution (<1 mum) and high sensitivity. ToF-SIMS is particularly suitable for 
      detection of molecules up to  approximately 2 kDa, including lipids, whereas larger molecules, 
      such as peptides and proteins, are fragmented during analysis, which makes them 
      difficult to identify. In this study, an approach for extending the molecular 
      detection capability of ToF-SIMS is presented, based on the specific binding of 
      functionalized liposomes to molecular targets on the sample surface and 
      subsequent detection of the liposomes by ToF-SIMS. Furthermore, by using 
      different recognition elements conjugated to liposomes with different lipid 
      compositions, simultaneous detection of different targets was accomplished. This 
      multiplexing capability was investigated for two types of recognition elements 
      (antibodies and cholera toxin) and for target molecules immobilized on surfaces 
      using two frequently applied surface functionalization strategies: a supported 
      lipid bilayer aimed to mimic a cell membrane and a polyethylene glycol modified 
      surface, commonly employed in bioanalytical sensor applications. The efficacy of 
      the conjugation protocols and the specificity of the recognition mechanism were 
      confirmed using quartz crystal microbalance with dissipation monitoring, while 
      fluorescence microscopy was used to validate the ToF-SIMS data and the 
      reliability of the freeze-drying step required for ToF-SIMS analysis. The results 
      demonstrated specific binding of the two types of liposomes to each target and 
      showed a concentration-dependent binding to the targets on the different model 
      surfaces. In particular, the possibility to use the contrasts in the mass spectra 
      of SIMS to identify the concentration dependent coverage of different liposomes 
      opens up new opportunities for multiplexed detection and quantification of 
      molecules at biotechnology relevant interfaces.
FAU - Wogelred, Louise
AU  - Wogelred L
AD  - RISE Research Institutes of Sweden, P.O. Box 857, SE-50115 Boras, Sweden and 
      Department of Physics, Chalmers University of Technology, SE-41296 Goteborg, 
      Sweden.
FAU - Hook, Fredrik
AU  - Hook F
AD  - Department of Physics, Chalmers University of Technology, SE-41296 Goteborg, 
      Sweden.
FAU - Agnarsson, Bjorn
AU  - Agnarsson B
AD  - Department of Physics, Chalmers University of Technology, SE-41296 Goteborg, 
      Sweden.
FAU - Sjovall, Peter
AU  - Sjovall P
AD  - RISE Research Institutes of Sweden, P.O. Box 857, SE-50115 Boras, Sweden and 
      Department of Physics, Chalmers University of Technology, SE-41296 Goteborg, 
      Sweden.
LA  - eng
PT  - Journal Article
PT  - Research Support, Non-U.S. Gov't
DEP - 20180315
PL  - United States
TA  - Biointerphases
JT  - Biointerphases
JID - 101275679
RN  - 0 (Biological Factors)
RN  - 0 (Liposomes)
SB  - IM
MH  - Biological Factors/*analysis
MH  - Biosensing Techniques/*methods
MH  - Liposomes/chemistry/metabolism
MH  - Sensitivity and Specificity
MH  - Spectrometry, Mass, Secondary Ion/*methods
MH  - *Surface Properties
EDAT- 2018/03/17 06:00
MHDA- 2019/02/26 06:00
CRDT- 2018/03/17 06:00
PHST- 2018/03/17 06:00 [entrez]
PHST- 2018/03/17 06:00 [pubmed]
PHST- 2019/02/26 06:00 [medline]
AID - 10.1116/1.5019749 [doi]
PST - epublish
SO  - Biointerphases. 2018 Mar 15;13(3):03B413. doi: 10.1116/1.5019749.