Sachin A. Pishawikar

High-Throughput Screening (HTS) is an approach to drug discovery that has gained widespread popularity over the last two decades and has become a standard method for drug discovery in the pharmaceutical industry. Progress from traditional one-compound-at-a time approach, low throughput screening to high throughput screening involving fully automated robotic systems, enables testing of large numbers of compounds daily for different activities in miscellaneous areas of biology. HTS reveals screening of more than 100,000 samples per day. Compared to traditional drug screening methods, HTS is characterized by its simplicity, rapidness, low cost, and high efficiency. Identification of good hits using HTS can minimize the time span of drug discovery noticeably. However, synthetic chemistry for lead optimization and the low throughput of secondary assays for defining the crucial pharmacological properties of active compounds, limits the overall rate of identification of candidate molecules for clinical evaluation. Coupling of compound library with wide chemical diversity along with HTS shows massive drug discovery potential, but to be successful screening technique it depends on several factors. These include the number and quality of validated targets, the number and diversity of compounds in the collections, and the ability to screen these in a timely and cost effective manner using robust informative assays. In this review we have discussed the types of HTS assays, assay miniaturization automation and different detection techniques like fluorescence resonance energy transfer (FRET), fluorescence polarization (FP), homogeneous time resolved fluorescence (HTRF) etc.