Analytical and Bioanalytical Chemistry

, Volume 411, Issue 6, pp 1135–1142 | Cite as

Confining analyte droplets on visible Si pillars for improving reproducibility and sensitivity of SALDI-TOF MS

  • Qunyan Zhu
  • Fei Teng
  • Zhongshun Wang
  • Yalei Wang
  • Nan LuEmail author
Paper in Forefront


We present a universal method to efficiently improve reproducibility and sensitivity of surface-assisted laser desorption/ionization time of flight mass spectrometry (SALDI-TOF MS). In this method, the Si pillar array with unique surface wettability is used as substrate for ionizing analyte. The Si pillar is fabricated based on the combination of photolithography and metal-assisted chemical etching, which is of hydrophilic top and hydrophobic bottom and side wall. Based on the surface wettability of the Si pillar, a droplet of an aqueous analyte solution can be confined on the top of the Si pillar. After evaporation of solvent, an analyte deposition spot is formed on the top of Si pillar. The visible size of the Si pillar allows the sample spot to be easily found. Meanwhile, the diameter of the Si pillar is smaller than that of the laser, allowing the observation of all analyte molecules under one laser shot. Therefore, the reproducibility and sensitivity are highly improved with this method, which allows for the quantitative analysis. Furthermore, this method is applicable for different analytes dissolved in water, including amino acids, dye molecules, polypeptides, and polymers. The application of this substrate is demonstrated by analyzing real samples at low concentration. It should be a promising method for sensitive and reproducible detection for SALDI-TOF MS.

Graphical abstract


SALDI-TOF MS Improving reproducibility and sensitivity Minimizing sample spots Visible Si pillars Universality 


Funding information

This work was supported by the National Natural Science Foundation of China (No. 21673096).

Supplementary material

216_2018_1565_MOESM1_ESM.pdf (9.9 mb)
ESM 1 (PDF 10182 kb)


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Copyright information

© Springer-Verlag GmbH Germany, part of Springer Nature 2019

Authors and Affiliations

  1. 1.State Key Laboratory of Supramolecular Structure and Materials, College of ChemistryJilin UniversityChangchunChina

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