Skip to main content

Separation Technologies

GC

Hewlett Packard HP-5890 with HP7673 autosampler and flame ionization detector

Gas Chromatography

A gas chromatographer vaporizes a sample and then passes it through a column. The rate at which the molecules will pass through the column depends on their attraction to it. For example, in a non-polar column, larger molecules will be more strongly attracted and hence will take longer to make their way through the column than smaller ones. This allows us to see how many different substances are contained in a sample, their relative abundances, and some information regarding their chemical nature.

Orgo GC

Gow Mac GC with thermal conductivity detectors


Mass Spectrometry

A mass spectrometer breaks a molecule into fragments and imparts them with a small amount of charge which then travel through the machine at a rate related to their mass. Some small fraction of the molecules will typically make it through the spectrometer whole but having been imparted a charge. Thus, we learn what the molecular weight of the molecule is. Seeing how it is broken apart also gives some insight as to the molecule's overall structure.

 

Orgo GCMS

Thermo Electron Focus DSQ with GC, EI source, and Quadrupole detector


HPLC

Agilent 1100 Series HPLC with quaternary pump, degasser, autosampler, variable wavelength detector, refractive index detector and Chemstation Data System

High Performance Liquid Chromatography

HPLC works in a manner very similar to gas chromatography. As the sample passes through the chromatography column, an equilibrium is established in which the molecules go from being bound to the column and passing through it in the "mobile phase". This equilibrium will be dependent on the relative attraction of the molecules to the column. Thus, we can separate our sample into its various components and determine how much of each is present.

Grand Valley State operates several HPLCs including Agilent 1100 Series HPLC with quaternary pump, degasser, autosampler, variable wavelength detector, refractive index detector and Chemstation Data System, Hitachi 7000 series HPLC with both variable wavelength detector and and refractive index detection, 4 Hitachi HPLC systems with variable wavelength detector and autosampler, 2 currently set up for normal phase with chiral columns, Shimadzu HPLC system with variable wavelength detector and Ion Chromatography System with Waters pump, Alltech Ion Suppressor and Conductivity Detector

 

not an HPLC

ion chromatography

Ion Chromatography System with Waters pump, Alltech Ion Suppressor and Conductivity Detector