Equipment

Tue, 2012-04-24 00:11 -- science

Instruments and Equipment

 

Students use research-grade instrumentation at AU to prove the chemical structure of compounds never before synthesized, or identify the heavy metal content in ancient artifacts, historical texts and everyday products. Opportunities in industry, research and graduate school await the students with understanding and experience in using chemistry instrumentation.

Fourier Transform-Infrared Spectroscopy

AU has a Varian 800 Scimitar™ FT-IR with Pike MIRacle™ single reflection ATR (attenuated total reflectance).

Bonds in molecules vibrate at a frequency based on the bond strength and polarity. FT-IR spectroscopy can determine the type of bonds present in a molecule by the frequency of energy they absorb. It is used by chemists to identify the presence of functional groups in a molecule.

X-Ray Fluorescence Spectroscopy

Sometimes student projects turn into valuable pieces of instrumentation for the department, such our XRF.

X-rays are focused on a material of interest. These bombarding x-rays cause the object of interest to emit characteristic x-rays that are unique to each element, thus allowing elemental analysis. Students have utilized this equipment on projects involving ancient artifacts, historical texts and identifying lead in toys.

Atomic Absorption Spectroscopy

AU has a Varian AA240 Fast Sequential AAS.

Most metals and metal ions in samples that can be dissolved in solution are readily analyzed with AA. The AA 240FS draws a solution up into an atomizing chamber where the droplets are drawn into a flame. Light of a specific wavelength for that metal is passed through the sample and is absorbed. The degree to which it is absorbed corresponds to the amount of metal species present.

Gas & Liquid Chromatography

AU has several different types of chromatographs: GC-FID (flame ionization detector), GC-MS (mass spectrometer detector), HPLC (high performance liquid chromatography with ultraviolet diode array detector) as well as TLC (thin layer chromatography) and various other column type exchanges.

Students at AU have used these various types of chromatography to perform research analyzing a range compounds from pesticide residues on apples to particulate matter left after fires where arson was suspected.

Fluorescence Spectroscopy

AU has a Cary Eclipse Fluorescence Spectrophotometer.

One of the most sensitive instruments in our lab relies on a molecule’s ability to fluoresce. It can be used in a computer controlled ratio mode as a fluorescence spectrophotometer with measurement modes for fluorescence, phosphorescence, chemiluminescence and bioluminescence. It also has a temperature control probe for analysis at conditions other than room temperature in kinetic studies.

Ultraviolet-Visible Spectroscopy

AU has a Cary Model 1E UV-Visible Spectrophotometer.

This is a double beam spectrophotometer capable of making concentration measurements, scans and kinetic analysis.

Fourier Transform-Nuclear Magnetic Resonance Imaging Spectroscopy

AU has an FT Anasazi upgrade on a 60 MHz EFT NMR with a 1H probe and a 13C probe.

Atoms with an odd number of nucleons, like 1H and 13C behave like magnets. When a sample is pulsed with radiofrequency energy, they effectively line up with the magnetic field then relax giving a signal that is characteristic of their environment. In the medical field, this technique is called MRI (magnetic resonance imaging).

A 1H NMR gives information about the structure of a molecule. It gives the number and kinds of hydrogen attached to it. Left shows a plot of areas where different types of hydrogen produce signals and a spectrum.