Sol-gel-derived silver-nanoparticle-embedded thin film for mass spectrometry-based biosensing

Area of Science:

• Materials Science
• Analytical Chemistry
• Nanotechnology

Background:

• Biosensors are crucial for detecting various chemical compounds.
• Matrix-free laser desorption ionization mass spectrometry (LDI-MS) offers simplified analysis.
• Silver nanoparticles (AgNPs) show potential in enhancing MS performance.

Purpose of the Study:

• To develop a porous silver-nanoparticle (AgNP)-embedded thin film biosensor.
• To evaluate its efficacy as a matrix-free LDI-MS biosensor.
• To demonstrate its applicability for analyzing peptides, lipids, and sterols.

Main Methods:

• Sol-gel method for fabricating AgNP-embedded thin films.
• UV laser irradiation (337 nm) for desorption and ionization.
• X-ray photoelectron spectroscopy (XPS) and UV-vis spectroscopy for composition analysis.
• Field-emission scanning electron microscopy (FE-SEM) for surface morphology study.

Main Results:

• The AgNP-embedded thin films functioned as effective matrix-free LDI-MS biosensors.
• Efficient desorption and ionization of peptides, triglycerides, and phospholipids were achieved.
• Preferential ionization of sterols from complex lipid mixtures was demonstrated.
• XPS confirmed AgNP composition with a characteristic binding energy.

Conclusions:

• The developed AgNP-embedded thin film biosensor is a promising tool for matrix-free LDI-MS.
• It simplifies the analysis of diverse biomolecules, including sterols.
• This approach offers a streamlined method for analyzing sterols in complex biological samples.