MALDI MS sample preparation by using paraffin wax film: systematic study and application for peptide analysis
Junhua Wang1, Ruibing Chen, Mingming Ma
1School of Pharmacy and Department of Chemistry, University of Wisconsin-Madison, 777 Highland Avenue, Madison, Wisconsin 53705-2222, USA.
Analytical Chemistry
|January 15, 2008
Summary
Parafilm M enhances matrix-assisted laser desorption/ionization mass spectrometry (MALDI MS) by repelling solvents, concentrating samples for better detection. This hydrophobic surface improves sensitivity and spectral quality for analyzing low-abundance peptide mixtures.
Area of Science:
- Analytical Chemistry
- Biochemistry
- Mass Spectrometry
Background:
- Hydrophobic sample supports improve matrix-assisted laser desorption/ionization mass spectrometry (MALDI MS) sensitivity and spectral quality.
- These techniques concentrate samples by minimizing area through solvent-repellent surfaces.
Purpose of the Study:
- To evaluate Parafilm M as a hydrophobic substrate for enhanced MALDI MS analysis.
- To optimize sample preparation for low-abundance peptide mixtures using Parafilm M.
Main Methods:
- Utilized Parafilm M as a hydrophobic sample support for MALDI MS.
- Employed nanoliter-volume deposition with 2,5-dihydroxybenzoic acid matrix.
- Optimized sample volume, solvent composition, and film treatment for dilute peptide samples.
Main Results:
- Parafilm M effectively repelled polar solvents (water, methanol, acetonitrile), enabling diverse sample preparation protocols.
- Nanoliter-volume deposition created small matrix spots (approx. 400 microm) on the film.
- Achieved detection of nanomolar concentration peptide mixtures using MALDI time-of-flight and Fourier transform ion cyclotron resonance mass spectrometers.
Conclusions:
- Parafilm M serves as an effective hydrophobic substrate for MALDI MS.
- The combination of Parafilm M and nanoliter-volume deposition significantly improves sensitivity and spectral quality for complex peptide mixture analysis.
