Poster Presentations
Day 2, June 11（Thu.） Room P (5F 501+502)
- 2P-04（1D-O2-1530）
Fabrication of a Thermal-Conductivity-Controlled SALDI Device Featuring Si/Metal Composite Nanopillar Structures
(1Hokkaido Univ., 2Hokkaido Univ.)
oYusuke Fujii1, Yasutaka Matsuo2
We fabricated Silicon(Si), gold(Au), and Si/Au based nanopillar Surface assisted laser desorption/ionization (SALDI) substrates with tunable pillar diameter and pitch using electron-beam lithography, sputter deposition, and dry etching. Glycine was deposited on the structures and its ions were analyzed by MALDI-TOF-MS to quantify the ion intensity and the minimum laser power required for detection (the ionization threshold). Finite-element simulations (COMSOL Multiphysics) were performed to estimate transient temperature rises under laser irradiation and to evaluate how material combinations and geometry influence ionization. The highest ionization efficiency was obtained for substrates with a Si base and Au nanopillars, indicating that heterointerfaces can enhance SALDI performance. Simulations suggested that combining strongly absorbing Au with low-thermal-conductivity Si promotes efficient local heating, but when experimentally measured reflectance (absorption) was incorporated, temperature rise did not always correlate with ion yield. These results imply that additional factors - such as heat transfer across the heterointerface and other interfacial effects - also govern ionization. We discuss the key determinants of ionization efficiency in heterogeneous micro/nanostructured SALDI surfaces and provide guidelines for material optimization.