High-Throughput Small Molecule Identification Using MALDI-TOF and a Nanolayered Substrate

Abstract

Encoderless combinatorial chemistry requires high-throughput product identification without the use of chemical or other tags. We developed a novel nano-layered substrate plate and combined it with a microarraying robot, matrix-assisted laser desorption/ionization (MALDI) mass spectrometry, and custom software to produce a high-throughput small molecule identification system. To optimize system performance, we spotted 5 different chemical entities, spanning a m/z range of 195 to 1338, in 20,304 spots for a total of 101,520 molecules. The initial spot identification rate was 99.85% (20,273 spots), and after a proofreading algorithm was added, 100% of 20,304 spots and 101,520 molecules were identified. An internal recalibration algorithm also significantly improved mass accuracy to as low as 45 ppm. Using this optimized system, 47 different chemical entities, spanning a m/z range of 138 to 1,592, were spotted over 5,076 spots and could be identified with 100% accuracy. Our study lays the foundation for improved encoderless combinatorial chemistry.

High-Throughput Sorting and Placement of One-Bead–One-Compound (OBOC) Libraries from Bulk to Single Wells in Organic Solvent

“…With a median deposit accuracy of 97% and plate processing time of 11 minutes, the bead sorting station can process over twenty plates or approximately 8,500 beads in under five hours. When incorporated into a high-throughput small molecule synthesis and screening program, 14–16 the instrument we describe has the potential to accelerate drug development and high-throughput screening.…”

Rapid and Facile Microwave‐Assisted Surface Chemistry for Functionalized Microarray Slides

“…Previously, we developed an automated, high-throughput sample spotting technique using a microarraying robot to generate up to 5,076 chemical spots on to a single glass slide. [26] To conjugate a series of ligands covalently, we re-optimized the spotting buffer to include 70% glycerol in DMSO supplemented with diisopropylethylamine (DIEA) for aprotic conditions or 70% glycerol in PBS (pH 8) for protic conditions, resulting in homogeneous 300-μm diameter spots. Accurately aligned fluorescent spots were formed with an excellent signal-to-background ratio (Figure 3b).…”

Analysis of carbohydrates and glycoconjugates by matrix‐assisted laser desorption/ionization mass spectrometry: An update for 2011–2012

“…A method using a novel nanolayered substrate plate combined with a microarraying robot, custom software, and MALDI‐TOF MS for high‐throughput small molecule identification, exemplified with, among other compounds, the carbohydrate kanamycin ( 50 ), has been developed by Lee et al (). To optimize system performance, five different compounds, spanning the m/z range of 195–1338, were spotted on 20,304 spots.…”