The Analytical Chemistry team has continued to perform the core responsibility of purifying samples with material in the range of milligrams to grams. Major and minor components (< 0.1 percent) have been isolated for additional testing and characterization. The teams automated sample processing protocol allows for dispensing into 1D barcoded vials, Matrix 2D barcoded tubes and/or 96-well plates for efficient tracking, storing and testing. The entire process from receiving the sample to final plating is completed within one week. While the group uses a variety of liquid chromatographs to determine identity and purity, single quadrupole liquid chromatography/mass spectrometry instrumentation is utilized for high-throughput automated analysis. Due to the wide variety of analytes tested, the teams range of analytical detectors includes ultraviolet (UV), mass spectrometry (MS; positive and negative mode), and evaporative light scattering detector and fluorescence (ELSD). Time-of-flight mass spectrometry (TOF/MS) is employed to achieve formula confirmation and identity determination of unknowns. The chemical and enantiomeric purity of chiral compounds is routinely determined within the groups full-scale chiral laboratory. Methods development with the chiral chromatography screening protocol involves the utilization of various chiral stationary phases in conjunction with multiple mobile phase conditions. The use of an inline chiral detector allows for the determination of relative optical rotation. Sample purification on a scale of up to hundreds of milligrams is possible. We continued to expand our chiral purification capabilities to accommodate the increasing number of chiral being synthesized at NCATS. As part of our vibrational circular dichroism (VCD) spectrometry platform, we in the process of deploying up conformational analysis software on our high-performance computing (HPC) cluster. This will greatly reduce the computing time needed to generate predicted VCD spectra for comparison with experimental results. Additionally, this software can be applied to the computer-assisted 3D structure elucidation (CASE-3D) platform we are developing, which will utilize isotropic and anisotropic NMR data. The expansion of DPIs focus beyond small molecules to alternate therapeutic modalities has necessitated an increase in our NMR and MS analytical capabilities through the acquisition and incorporation of more advanced instrumentation and techniques in order to detect, identify, quantify, and validate these new chemical entities. For NMR spectroscopy, this has involved the development and implementation of routine methods for the analysis of peptides. We are also investigating protein-protein interactions (PPI) through ligand-protein binding experiments. For mass spectrometry, we recently installed an Orbitrap Fusion Lumos MS system, which allows us to perform top-down proteomics including post-translational modification analysis. The ability to perform intact protein analysis has helped drive the antibody-drug conjugate (ADC) screening project. Furthermore, we have developed an automated 384-well plate proteomic sample preparation platform using the Agilent AssayMAP Bravo liquid handler. This protocol reduces cost and improves efficiency for biomarker discovery and high-throughput drug screening. Due to the increased demand for biological screening using the RapidFire high-throughput mass spectrometry system, we are purchasing a second RapidFire system to meet our ever-growing workload and move projects forward at a much faster pace. The Sample Management and Resource Tracking (SMART) laboratory information management system (LIMS), continues to be utilized at DPI for sample submission, compound purification, compound processing, sample registration, compound inventory, sample tracking, data retrieval, and data management. Functionality is added to improve efficiency and productivity based on expanding and changing scientific needs. As part of our ongoing effort to migrate SMART onto a unified platform, we are working with the DPI Informatics group to integrate G-SRS, a chemical registration and management software developed at NCATS and currently utilized by the FDA, which will supplant our current outdated registration system. Also, the involvement of NCATS in the HEAL Initiative required us to create processes and protocols related to the purification and management of DEA controlled substances. As part of the ASPIRE program, the Analytical Chemistry group has begun the creation of an automated purification platform. Early stages of this endeavor look to optimize current purification processes and connect various islands of automation in an efficient manner. The end goal is a fully autonomous system, which can be integrated into an automated synthesis platform. Finally, SMART Consumables, Acquisitions, and Reagent Tracker (SmartCART), an order submission and management system originally developed for DPI Chemistry, has been re-branded as Scientific Ordering System (SOS) and is now the primary system for the requisition, organization, and management of all orders at DPI. Continued expansion of functionality, as well as development of direct interfacing with POTS, will allow SOS to expand its usage to all NCATS to better manage spending on a project-by-project basis.
| Liu, Li; Tang, Manshu; Walsh, Martin J et al. (2015) Structure activity relationships of human galactokinase inhibitors. Bioorg Med Chem Lett 25:721-7 |
