Academic Director: Kevin MacKenzie, Ph.D.
Co-Director: Feng Li, Ph.D.
Operations Director: Kimberly Kerlec, B.S.

Overview

The NMR and Drug Metabolism Core at Baylor College of Medicine offers tools to support the discovery, synthesis, screening, optimization, metabolism and pharmacokinetics of small molecule ligands or lead compounds. Our 600 and 800 MHz Bruker nuclear magnetic resonance (NMR) spectrometers are available for unassisted use by trained users, and user training in simple 1D and 2D NMR data acquisition and analysis is also available. Expert services are available to determine small molecule identity or conformation, to identify and quantify metabolites, to determine macromolecular structure or detect perturbations upon ligand binding, or to screen compound libraries against purified targets. We investigate the metabolism, metabolic stability, and pharmacokinetics of small molecular weight compounds using liquid chromatography-mass spectrometry (LC-MS and MS/MS). In addition to analyzing biological fluids or tissues, we assay stability in liver microsomes and perform reaction phenotyping against an array of CYP450s. Core personnel provide advice on the use of the supported methods for a wide variety of applications and assistance is available in project experimental design and data analysis.

NMR Facility and Services

Unassisted NMR usage: access for trained users. Users with expertise in NMR data acquisition can schedule instrument time to perform unassisted analysis, using standard 1D and 2D pulse sequences, after one or several hour-long training sessions (depending on previous experience).

Assisted NMR usage: fee-for-service data acquisition and analysis. Research groups lacking NMR expertise can arrange for core personnel to acquire and analyze NMR data to identify or determine the conformations of small molecules, to identify and quantify metabolites, or for feasibility studies in ligand/target screening, mapping of ligand/protein interactions, or NMR structure determination. Consult core personnel for advice on experimental design.

Target-directed ligand binding and compound library screening. NMR can be used to quantify ligand binding or to screen libraries of hundreds to thousands of compounds against purified targets. Compound libraries and the DNA-encoded (DEC-Tec) platform are available through the BCM Center for Drug Discovery. Core personnel are available to discuss the relative merits of different approaches and to analyze the resulting data. Through the Center for Drug Discovery, follow-up validation and diversification of screening or selection hits can be performed based on available structure-activity relationship data.

Drug Metabolism and Pharmacokinetics Services

We have developed rapid, efficient methods to investigate drug metabolism, stability, pharmacokinetics, and metabolic product identification to guide the optimization of lead compounds. Our state-of-the art LC-MS and expertise will enable us to apply or design methods to meet your needs. We provide chemical entities analysis to quantify drugs in fluids or tissues, microsomal stability assays to predict in vivo clearance, reaction phenotyping to identify the enzymes involved and predict possible drug-drug interactions, drug metabolite identification (from liver microsomes or in vivo studies), and in vivo pharmacokinetic profiles including oral bioavailability and tissue distribution in 15 rodent target organs.

Major Equipment

The Avance III HD 800 MHz spectrometer (320x240)
The Avance III HD 800 MHz spectrometer has a high sensitivity QCI CryoProbe™.

Avance III HD 800 MHz spectrometer operates three RF channels plus deuterium using a quadruple resonance inverse detection QCI CryoProbeTM (5 mm sample diameter) equipped with z-gradients. The system allows very high sensitivity observation of 1H or 19F with 15N, 31P and 13C decoupling; alternatively, it supports high sensitivity 13C observation with 1H and 15N decoupling.  The SampleJet dual-mode automated sample changer accepts a mix of tube diameters (1, 1.7, 3, and 5 mm) for either standard 7” tubes or 4” SampleJet tubes in up to five racks of 96 samples.

Avance III HD 600 MHz spectrometer
Avance III HD 600 MHz spectrometer

Avance III HD 600 MHz spectrometer operates two RF channels (plus deuterium) using an inverse triple resonance probe (5 mm sample diameter, 1H observe, 13C and 15N decoupling, 2H lock) with automatic tuning and matching and an actively shielded z-gradient coil.  The SampleXpress™ sample changer with bar-code reader supports automation of up to 60 sample tubes (1.7 mm to 5 mm ODs; 100 mm to 228 mm lengths).

Agilent 6490 Triple Quadrupole Mass Spectrometer
Agilent 6490 Triple Quadrupole Mass Spectrometer coupled to an HPLC system (LC-QQQ MS).

Agilent 6490 triple quadrupole mass spectrometer (QQQ MS) coupled to an Agilent 1290 Infinity LC System (HPLC) operates in both positive and negative modes with electrospray ionization. The system has been widely used for microsomal stability screening, drug metabolism, and pharmacokinetics. The instrument allows quantitative and specific determination of the concentrations of drugs or other compounds in various biomaterials (serum, tissue, urine etc.) using the multiple reaction monitoring (MRM) method.