Laser desorption/ionization mass spectrometry-based compositional analysis of Au–Ag nanoplates synthesized by galvanic replacement and their application for small molecule analysis.

Graphical abstract Highlights • Synthesis of Au–Ag nanoplates with a controlled atomic composition. • Their atomic analysis with laser desorption/ionization mass spectrometry. • Effect of their shape and optical property on small molecule analysis. • The optimization of Au–Ag nanoplates for small molecule analysis. Abstract This paper demonstrates that laser desorption/ionization time-of-flight mass spectrometry (LDI-TOF-MS) can be utilized to analyze the relative atomic composition and photothermal conversion properties of Au–Ag alloy nanoplates synthesized by galvanic replacement reactions. Using Au–Ag alloy nanoplates with various shapes, it is found that the porous structures of the nanoplates affect their photothermal conversion efficiency more than their laser energy absorption capacity does. Based on these findings, the optimized Au–Ag alloy nanoplates can be applied to LDI-TOF-MS of small molecules. [ABSTRACT FROM AUTHOR]