U.S. flag

An official website of the United States government, Department of Justice.

NCJRS Virtual Library

The Virtual Library houses over 235,000 criminal justice resources, including all known OJP works.
Click here to search the NCJRS Virtual Library

Chemical Analysis of Macromolecular Particles Using Two-Dimensional High-Performance Liquid Chromatography (HPLC), Illustrated by Polymeric Automobile Direction Indicator Lenses (DILs)

NCJ Number
131247
Journal
Journal of Forensic Sciences Volume: 36 Issue: 4 Dated: (July 1991) Pages: 1010-1019
Author(s)
K Kretschmer; W Helbig
Date Published
1991
Length
19 pages
Annotation
The use of two-dimensional size exclusion liquid chromatography (SEC)/reversed phase chromatography (RPC) together with the detector combinations in series for the analysis of fragments of automobile direction indicator lenses (DIL) is described.
Abstract
Samples of fragments of DILs from various automobile manufacturers were chromatographed after 50 milligram size samples were dissolved in dichloromethane. The SEC chromatograms were recorded using clear ultraviolet/RI detectors. Clear differentiation was obtained with the automobile model identified through DIL fragment analysis. In addition, the difference among the individual detection signals provided data on the polymers that were displayed at the exclusion limit. Chromatographic examinations of similar DIL fragments from automobiles of the same type suggested differences that were clearly separated by RPC of the SEC fractions which contained all low molecular weight compounds. The chromatograms recorded simultaneously at 2 different wavelengths, 254 and 280 nanometers, and contained a large amount of information sufficient for clear differentiation. These detectable quantitative differences in polymer compositions are attributed to deviations during manufacturing, processing operation, or weathering conditions. This methodology allows analysis of fragments of automobile DIL from different origins for their content of low-molecular weight substances or their subpolymeric components. 4 tables, 4 figures, and 23 references (Author abstract modified)

Downloads

No download available

Availability