Laser Desorption/Ionization on Au@TiO₂ Core@Shell Nanostars for Mass Spectrometric Analysis of Small Molecules

Area of Science:

• Nanomaterials Science
• Analytical Chemistry
• Surface Chemistry

Background:

• Developing novel nanomaterials is crucial for advancing analytical techniques.
• Laser Desorption/Ionization Time-of-Flight Mass Spectrometry (LDI-TOF-MS) requires efficient matrices for sensitive analysis.
• Existing matrices like spherical gold nanoparticles (Au NPs) have limitations in sensitivity and reproducibility.

Purpose of the Study:

• To synthesize and characterize novel core@shell nanostars (Au@TiO2 NSs) for LDI-TOF-MS applications.
• To evaluate the performance of Au@TiO2 NSs as a matrix for analyzing small molecules and synthetic polymers.
• To compare the analytical capabilities of Au@TiO2 NSs with conventional spherical Au NPs.

Main Methods:

• One-pot synthesis of Au@TiO2 nanostars without reducing or surface-controlling agents.
• Characterization of synthesized nanostructures using spectroscopic and microscopic techniques.
• LDI-TOF-MS analysis of small molecules and polymers using Au@TiO2 NSs and spherical Au NPs as matrices.

Main Results:

• Au@TiO2 NSs exhibit strong UV absorption due to the core-shell interaction.
• Enhanced LDI-TOF-MS performance with Au@TiO2 NSs, showing improved signal reproducibility and reduced background interference.
• Significant improvements in the limit of detection and dynamic range for various analytes compared to spherical Au NPs.

Conclusions:

• Au@TiO2 NSs are effective optochemical matrices for LDI-TOF-MS.
• The unique nanostar morphology and core@shell structure contribute to superior analytical performance.
• Au@TiO2 NSs represent a promising advancement for the sensitive and reproducible analysis of small molecules and synthetic polymers.