Prestructured MALDI-MS Sample Supports

摘要

Prestructured MAU)I-MS sample supports have been developed that simplify high-throughput analysis of bio-molecules and improve the detection sensitivity. The mass spectrometric sample support is coated with a thin layer of hydrophobic Teflon that carries an array of 200-pm gold spots, which provide hydrophilic sample anchors. Each transferred sample droplet contacts one anchor, on top of which, after solvent evaporation, the sample is exclu-sively deposited due to the strongly water repellent nature of the Teflon surface. The initial matrix concentration is kept low, enabling sample up-concentration by more than 2 orders of magnitudes before crystallization commences. As a result, the detection sensitivity is improved as documented by mass spectra recorded from 100 amol of various peptides, 1 fmol of a DNA 20 mer, and 5 fmol of a 130 bp PCR product. Size and spacing of the hydro-philic anchors are optimized for MALDI-MS performance (sample spot size laser irradiation spot size), for short analysis times (predetermined sample coordinates), and for high throughput sample preparation (sample anchor array according to the 1536 microtiter plate format).