|
Home >
Technical Articles >
NMR
|
|
NMR (nuclear magnetic resonance) spectroscopy has long been an invaluable analytical method in industry for verification of chemical synthesis and compound characterization. The power of NMR spectroscopy is truly unparalleled in the arena of structural identification of organic and biochemical compounds. In combination with other services already offered by Bodycote, |
including Fourier Transform Infrared Spectroscopy (FTIR), elemental analysis and mass spectrometry, NMR will prove particularly useful to projects aimed at identification of chemical and pharmaceutical unknowns. Our NMR services will be targeted primarily to corporate customers in the biotechnology, pharmaceutical, specialty chemical, nutraceutical, personal care, oil and petrochemical industries. |
NMR - IntroductionNMR spectroscopy uses radiofrequency radiation to induce transitions between different nuclear spin states of samples in a magnetic field. NMR spectroscopy can be used for quantitative measurements, but it is most useful for determining the structure of molecules (along with FT-IR and mass spectrometry). The utility of NMR |
spectroscopy for structural characterization arises because different atoms in a molecule experience slightly different magnetic fields and therefore transitions at slightly different resonance frequencies in an NMR spectrum. Furthermore, splittings of the spectral lines arise due to interactions between different nuclei, which provides information about the proximity of different atoms in a molecule. A typical NMR spectrum is shown in Figure 1. |
Our NMR SystemThe NMR system that will be installed in the Santa Fe Springs facility later this year will operate at 500 MHz (resonance frequency for 1H). It will have capabilities to study 1H and other nuclei (13C, 31P, 29Si, 19F, 2H, etc.). The new NMR spectrometer will be capable of analyzing samples in solution state (by the majority of modern 1D and 2D NMR experiments) and in solid state (by CP/MAS, cross polarization/magic-angle-spinning spectroscopy). The instrument will have variable |
temperature capabilities (ranging from -80 °C to +150 °C for solutions, and from -45 °C to +110 °C for solids). Figure 2 is an example of the main components of the NMR spectrometer, namely, the superconducting magnet, the console holding the electronics, and the computer workstation. The connectors for the various nuclei on the two probe heads (the 'antennas') are depicted in the bottom insets. The probe heads are inserted at the bottom; the sample, in an NMR glass tube (see top inset), is injected at the top of the magnet. |
Figure 2. NMR spectrometer with peripherals. Insets: Probe heads and NMR sample tube.
Dr. van HalbeekThe NMR Facility in Santa Fe Springs will be directed by Herman van Halbeek, Ph.D. Before joining Bodycote, Herman was Director of the Analytical Glycotechnology Core Facility at UC San Diego (1998-2003) and Director of NMR Science and Technology at the College of Chemistry’s NMR Facility at UC Berkeley (2003-2007). His NMR |
expertise ranges from synthetic organic and inorganic chemistry to biological chemistry (carbohydrates, peptides, natural products) and structural biochemistry to material science. During his academic career, he collaborated with many industrial clients, providing NMR structural characterization services to a number of laboratories in the pharmaceutical and biotechnology industry. |
NMR ServicesWe plan to offer, first of all, a number of “routine” NMR services, ideal for product quality control, structure verification, structure elucidation of smaller molecules and/or evaluation of compound purity (including, for example, the purity check of heparin, recently mandated by FDA (see Figure 3a and 3b, as well as any other NMR tests mentioned in USP and EP monographs). Examples of solution-state NMR experiments in this category are: · 1D spectra of 1H, 13C, 19F and 31P · 2D {1H,1H} COSY, TOCSY and 2D {1H,13C} HSQC and HMBC
|
Solid-state NMR is commonly used in the
analysis of polymorphs, particularly in the pharmaceutical area. Our
routine solid-state NMR services will include CP/MAS spectra of
13C, 29Si, 31P etc. We also look forward
to assisting customers who have needs for more advanced NMR applications
aimed at, for example, complete characterization of
compounds of modest structural complexity. Bodycote’s NMR services are expected to benefit a wide range of customers in chemistry, biochemistry, pharmacy, life sciences, and material sciences. More specifics will follow in our next issue of Analytical Digest. Please contact Herman van Halbeek 562-948-2225 (ext 614) if you have any questions regarding NMR services that may be of interest to your company. |
