Implementation of GC-MS in Instrumental Methods of Analysis

by Jeffrey Ashley, Philadelphia University (ashleyj@philau.edu)

This course has been modified to expand the lecture material to include more theory of mass spectrometry, incorporate additional analyses of acquired spectra, and facilitate a laboratory experiment highlighting the analysis of an unknown and quantifying the sample using the internal standard method. A detailed discussion of the different components of our GC-MS is given and students are expected to identify spectra based on fragmentation patterns and the ion source used (e.g., negative chemical ionization vs. electron impact).  With this base knowledge of GC-MS, students then participate in a 3 hour hands-on laboratory that: 1) further acquaints them with GC-MS hardware and software, 2) introduces them to the concept of an internal standard as a means of quantifying organic analytes, and 3) requires them to determine which polycyclic aromatic hydrocarbon (PAH) is contained in their 'unknown' solution and at what concentration.  The lab is entitled "Identification of Polycyclic Aromatic Hydrocarbons (PAHs) using Gas Chromatography-Mass Spectrometry and Quantification using the Internal Standard Method".

Click HERE to see a pdf file containing this laboratory exercise.

This lab was developed through funding from NSF (DUE# 0126468 - Implementing Guided-inquiry Laboratories Utilizing Gas-chromatography Mass-spectrometry in the Chemistry/Biochemistry Majors Sequence)