JCE Online Journal of Chemical Education
 | Subscriptions  | Software Orders  | Support  | Contributors  | Advertisers  | 

JCE Print

JCE Digital Library

JCE Software

Only@JCE Online

About JCE


  Home > JCE Print > Journal of Chemical Education > Issues > 2003  > May  >
In the Laboratory
Classification of Vegetable Oils by Principal Component Analysis of FTIR Spectra
David A. Rusak, Leah M. Brown, and Scott D. Martin
Department of Chemistry, University of Scranton, Scranton, PA 18510

Cover
May 2003
Vol. 80 No. 5
p. 541

Abstract
Principal component analysis (PCA) of infrared spectra of different known vegetable oils is used to determine the identity of several unknown vegetable oils. The experiment requires access to an FTIR spectrometer with 1-cm-1 resolution and peak-finder capability, and a software package that can perform principal components analysis. Students acquire IR spectra of a series of known vegetable oils, choose spectral features to be analyzed by PCA, and create scatter plots of principal component scores of each oil. The unknowns are then analyzed, plotted, and identified based on their proximity to the knowns in principal component space. The PCA data analysis extracts the useful information from a highly correlated data set; it is easier to identify the unknown oils by looking at the plot of principal component scores than by looking at the IR spectra. This practical application of PCA in an instrumental laboratory introduces students to chemometrics and allows them to experience first-hand the utility of a multivariate data analysis technique.
Supplement
The experimental procedure and notes for the students are available.
*  Contents
*  Download
JCE2003p0541W.pdf

More Information
*  Citation
Rusak, David A.; Brown, Leah M.; Martin, Scott D. J. Chem. Educ. 2003 80 541.
*  Keywords
IR Spectroscopy; Laboratory Instruction; Statistics / Data Analysis; Analytical Chemistry; Instrumental Methods; Food Science; Lipids
*  History
Created:
Last Updated:
March 28, 2003
February 28, 2005
  Home > JCE Print > Journal of Chemical Education > Issues > 2003  > May  > Page 541


Subscriptions

JCE HS CLIC

Our Secondary School editors work hard to distill all the JCE materials to produce a fraction of particular interest to high school teachers. We call it CLIC.


Contributions Welcome
JCE welcomes your submission

Advertisers
In recent years we have worked hard to better match our advertisers with our readers. When shopping for chemistry education materials, visit our advertisers' WWW sites first.

Be An Ambassador
Take JCE along on your outreach missions. Copies of the Journal, guest access to JCE Online, our publications catalog, and more are available for your participants.