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. In an effort to analyze and separate any chiral compound type, we have expanded our capabilities by increasing the number of different chiral columns at our disposal over the past year. Additionally, utilization of our vibrational circular dichroism (VCD) spectrometer has allowed for determining the absolute configuration of isolated chiral compounds. This analysis is a collaborative effort with the DPI Informatics group to utilize their unparalleled molecular modeling capabilities. The Sample Management and Resource Tracking (SMART) system, our proprietary 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. As SMART is constantly evolving based on changing workflows and scientist needs, we have add required functionality while also streamlining user interfaces and the underlying scripting, which has led to a more robust and efficient system. In collaboration with NCATS OIT, we are in the process of transitioning SMART to a unified platform, which will enable better system control and higher integration with other software at DPI. Additionally, the SMART Consumables, Acquisitions, and Reagent Tracker (SMARTCART), which aids in the requisition, organization, and management of scientific related orders has be highly successful within DPI Chemistry. As such, the NCATS Acquisitions Workgroup has evaluated SMARTCART and we are working towards eventual adoption by all DPI scientific groups. Efforts continue in the establishment of our NMR fragment-based screening (FBS) program, which is a complementary approach to high-throughput screening in the discovery of chemical entities for development into therapeutics. With the integration of the fragment libraries complete, the team has begun the massive task of compiling reference spectra for each fragment within the collection. Analytical Chemistry maintains several collaborations conducting NMR ligand-protein binding studies as a complement to the established medicinal chemistry programs. Furthermore, we are expanding our capabilities to employ data fitting of multiple NMR parameters to perform configurational and conformational analysis of small molecules. Finally, we acquired a benchtop NMR for use within the Medicinal Chemistry labs. This system compliments our state-of-the-art NMR facilities by allowing for simple and expedient reaction monitoring to ensure formation of the desired product. With the successful development and set up of our state-of-the-art Mass Spectrometry laboratory, we have continued the expansion of analytical capabilities at NCATS. These include high-throughput MS sample analysis, peptide and protein analysis, multiple reaction monitoring, proteomics, and metabolomics. We have established collaborations for numerous ongoing projects at DPI with our involvement in assay development, methods optimization, mass spectroscopy experimentation, and data analysis. Utilization of the RapidFire high throughput sampling system provides us with a potential analysis capacity of 5000-10,000 samples per day (qualitative and quantitative) within various biochemical and ADME assays. Analytical Chemistry at DPI has access to thirteen mass spectrometry systems, which includes one GC-MS, eight HPLC-single Quad MS, one triple quad (QQQ) MS and three high resolution MS (two TOFs and one QTOF). We are currently writing papers for submission to peer-reviewed journals in order to highlight this extensive and high impact work.
| Liu, Li; Tang, Manshu; Walsh, Martin J et al. (2015) Structure activity relationships of human galactokinase inhibitors. Bioorg Med Chem Lett 25:721-7 |
