Automated high throughput multiple target screening of molecular libraries by microfluidic MALDI-TOF MS

Novel analytical techniques are demanded in parallel in the automated combinatorial library syntheses for accelerating the process of drug discovery. In this study, the integration of matrix-assisted laser desorption ionization time-of-flight mass spectrometry (MALDI-TOF MS) and robotics for simultaneously identifying lead compounds with activity against multiple enzyme targets has been shown. MALDI-TOF MS monitors the interactions between multienzyme targets and a library of compounds and then identifies individual compounds from molecular libraries that affect the enzymatic activities of multiplexed target molecules to catalyze the conversion of substrates to products, The novel mass spectrometry screening in high-density format (similar to 4,000 samples in a single 4.5 x 4.5 cm MALDI plate) provides much higher throughput over traditional screening approaches in terms of multiplex targets, atto-mole-level sensitivity, very low volume of samples required (10(-9)-10(-12) l), and data acquisition for each sample within ten sec. The microfluidic multiple target screening approach mass spectrometry was shown for discovery of enzyme inhibitors as potential lead compounds.