Two-dimensional graphene as a matrix for MALDI imaging mass spectrometry.

Area of Science:

• Analytical Chemistry
• Materials Science
• Biotechnology

Background:

• Matrix-Assisted Laser Desorption/Ionization - Imaging Mass Spectrometry (MALDI-IMS) is a powerful technique for spatial molecular analysis.
• Traditional MALDI-IMS often uses organic matrices that can lead to analyte diffusion and background noise.
• Graphene, a 2D material, has shown potential in various analytical applications due to its unique properties.

Purpose of the Study:

• To demonstrate the efficacy of a two-dimensional (2D) graphene matrix for MALDI-IMS.
• To evaluate the performance of 2D graphene as a matrix for analyzing biomolecules in biological tissues.
• To highlight the advantages of using 2D graphene over conventional matrices in MALDI-IMS.

Main Methods:

• A single layer of 2D graphene was directly applied onto rat brain sections and soybean leaves.
• Matrix-Assisted Laser Desorption/Ionization - Imaging Mass Spectrometry (MALDI-IMS) was performed using a Fourier transform ion cyclotron resonance (FT-ICR) mass spectrometer.
• Analysis focused on the desorption and ionization of various molecular classes from the tissue surfaces.

Main Results:

• The 2D graphene matrix enabled the desorption and ionization of several molecular classes from rat brain and soybean leaf tissues.
• Minimal background interference was observed when using the 2D graphene matrix.
• The solvent-free application of 2D graphene prevented analyte diffusion, preserving spatial molecular information.
• The elemental carbon nature of 2D graphene proved compatible with long MALDI-IMS experiments.

Conclusions:

• Two-dimensional (2D) graphene serves as an effective matrix for MALDI-IMS, offering advantages over traditional methods.
• The solvent-free application and minimal background interference make 2D graphene a promising matrix for high-resolution molecular imaging.
• This approach enhances the reliability and scope of MALDI-IMS for analyzing complex biological samples.