Shared Instruments Lab (SIL)
The Shared Instruments Lab (SIL) is a free resource for University students and faculty. The staff of the SIL do not run samples and are available for consultation and training only. Undergraduate, graduate, and post-doctoral students receive training and operate the instruments on a day-to-day basis. PI's wishing to use the instruments should have their students contact the Director of Instrumentation for training and account setup. The department also teaches instrumentation courses through the CHEM 707 class.
There are no fees to use the instrumentation, but consumables must be provided for by the PI. For example, if you want to run the LCMS you must provide columns, sample vials, and mobile phase or if you want to run the NMR you must provide the NMR tubes and deuterated solvents. Most consumables can be purchased from the research stockroom located in the basement of the Chemistry building.
Director of Instrumentation
The CEM Discover microwave can be used with sealed reaction vials (contact the Director of Instrumentation for information on purchasing appropriate reaction vials) or round bottom flasks with a condenser. This item must be checked out and brought to a PI's lab for use. The microwave must be used in a hood, especially if running experiments in a round bottom with a condenser.
Solid-State Nuclear Magnetic Resonance Spectroscopy
The Shared Instruments Lab currently operates one solid-state NMR, a 2-channel 400 MHz Tecmag Discovery with a NMR Service GmbH MAS H-X broadband probe that can rotate samples up to 18 kHz. The Discovery system is capable of running CP/MAS experiments using a 4 mm rotor.
The chemical shift that a molecule has for a particular nucleus is a function of alignment of the molecule to the external magnetic field. In liquid-state NMR the rapid rotation of a molecule in solution averages out the chemical shift to a single value called the isotropic chemical shift. In a solid-state powder sample every orientation of the sample relative to the external magnetic field is present. This can lead to peaks that are extremely broad with linewidths greater than 1000 Hz. To overcome this problem the sample is spun at the magic angle, 54.74 degrees. This averages out the chemical shift anisotropy (and dipolar couplings) and gives a high-resolution spectrum.
To spin stably within a few Hz, at a high rate, 9000-18,000 Hz, two 200-gallon compressed air tanks are used.
Liquid-State Nuclear Magnetic Resonance Spectroscopy
- A Varian 400-MR which is a 400 MHz NMR with an auto switchable probe setup for running 1H, 19F, 13C, and 31P experiments.
- A 2-channel 400 MHz Varian VNMRS with an ATB automation probe for running 1H, 19F, 13C, 15N, and 31P experiments. This NMR is equipped with an FTS unit for variable temperature experiments.
- A 3-channel 500 MHz Varian VNMRS with a wide variety of probes allows for the acquisition of virtually any NMR active nucleus. This NMR is equipped with a FTS unit for variable temperature experiments.
Electron Paramagnetic Resonance Spectroscopy
Electron paramagnetic Spectroscopy, or EPR for short, is used to study molecules and reactions that involve a species with an unpaired electron. Traditional NMR techniques yield little to no useful information on paramagnetic species due to the greatly accelerated relaxation rate of the NMR signal.
In 2011 the department acquired a Bruker EMXPlus EPR. This EPR is equipped with a helium recycling unit which allows for the acquisition of low-temperature EPR spectra without the need to constantly add liquid helium. The helium recycler significantly reduces the cost of operation for low-temperature experiments.
Bruker Smart APEX: Used to determine the structure of a compound from a crystal you've grown.
Agilent 7890A gas chromatograph coupled to a 5975C quadrupole mass spectrometer: This instrument has a 150 position Agilent 7603 autosampler and has EI only. It can be run without the mass spectrometer using a FID as the detector.
Varian CP-3800 gas chromatograph coupled to a Varian Saturn 2200 ion trap mass spectrometer: Setup for analyzing volatile solid samples using the Varian ChromatoProbe. The mass spectrometer can ionize compounds by CI or EI.
Agilent model G6230A high-resolution high-mass accuracy time-of-flight mass spectrometer: This instrument is suitable for final product characterization. It has a mass accuracy of 2 ppm and has ESI, APCI, and APPI ion sources. Samples can only be introduced via the infusion method using a syringe pump. Samples should be in the micro to nanogram per milliliter concentration range.
The Shared Instruments Lab has available a Waters Micromass ZQ quadrupole mass spectrometer suitable for routine reaction monitoring. It has the Waters Alliance e2695 HPLC unit which allows for separation of mixtures before analysis by the mass spectrometer. Samples can be introduced using either the HPLC autosampler or the syringe infusion method. The HPLC is equipped with a Waters XBridge C18 column for general public use; any other column must be provided by a PI.
We currently have two FT-IR's, both of which can be used with either the standard transmission plate or the ATR (Attenuated Total internal Reflection) in the sample compartment.
- Thermo Nicolet 6700 FT-IR: A high-resolution instrument that can scan all three ranges of the infrared spectrum, far (50-400 cm-1), mid(400-400 cm-1) and near (4000-10,000 cm-1), and has a diamond ATR. This IR is also purged to eliminate the CO2 peak from air.
- Thermo Nexus 470 FT-IR: A general purpose mid-IR instrument which can scan from 400-4000 cm-1 and has ZeSe and Ge ATR's.
Determine the polarisation direction of light or the optical rotation of a compound.
Jobin Yvon Horiba FluoroMax-3: a compact spectrofluorometer that offers the ultimate sensitivity in fluorescence investigations as well as features not found in most table-top fluorescence detection systems.
Shimadzu UV-2550: Following their introduction in 1995, the world's highest performance, easy-to-use Shimadzu UV-2401/2501 spectrophotometers are now even more powerful with the addition of the world's most advanced software. The University's Shimadzu UV-2550 features:
- low light stray
- high performance
- Analysis of multiple trace samples
Nanosurf EasyScan 2 with AFM and STM options:
- AFM: Atomic Force Microscope, images a surface by measuring the repulsion/attraction of a cantilever tip as the tip scans across the sample surface, generally more broadly applicable than STM.
- STM: Scanning Tunneling Microscope, images a surface by measuring the tunneling current between tip and surface, good only for conductors, generally better resolution than AFM.
Differential Scanning Calorimetry (DSC)
The basis for the DSC technique is that when a sample undergoes a physical transformation, such as a phase transition, more or less heat will be needed depending on whether the transformation is endothermic or exothermic. A DSC is able to accurately measure the heat absorbed or released during a transition. Some areas where DSC is used is in studying polymer and pharmaceutical formulations, liquid crystals, oxidation stability, and metallurgy.
The SIL offers the TA instruments model Q20 DSC.
Orec Ozonator, you supply oxygen in and it produces ozone.
An Agilent 7890 GC with FID (flame ionization detector) setup for chiral analysis only. Several capillary chiral columns are available for use.