Forensics Journal - Stevenson University 2011 | Page 24
STEVENSON UNIVERSITY
CONCLUSION
ABOUT THE AUTHOR
Julia M. Wikoff was born and raised in Southern Maryland. She earned her BS in chemistry
and minor in biology from Stevenson University (2006). During her time as an undergraduate at Stevenson, she worked for two
years on research projects lead by Dr. Timothy
Dwyer and Dr. Tracey Mason. She is currently working on her
master’s degree in Forensic Science at Stevenson University. For
the past year, she has been working as an intern in the Forensic
Science Division at the United States Secret Service. She also
works as a graduate assistant for the chemistry department at
Stevenson University.
The results show that solvent grades do have an effect on the separation and clarity of the ink components as well as deviations from
the Rf values; however, these two effects do not go hand-in-hand for
each solvent system combination. Once a laboratory has chosen the
grade of solvents used for thin-layer chromatography, they must keep
consistent solvent grades. The results also show that plates must be
run on the same day in the same tank for the results to stay consistent
for comparison. Alternate light sources should be used to view TLC
plates; the fluorescent bands can be viewed using any combination of
solvent grades for Solvent System I. Laboratories need to stay consistent with the grade of solvents that they use for thin-layer chromatography. If possible, the manufacturer of the solvents should also stay
consistent.
REFERENCES
1. ASTM. (2008). Standard Guide for Test Methods for Forensic
Writing Ink Comparison. ASTM International.
2. Bryan, E. (2010, May/June). Questioned Document Examination.
Evidence Technology Magazine, 8(3), 20-24.
3. Neumann, C., & Margot, P. (2010, September). Considerations
on the ASTM Standards 1789-04 and 1422-05 on the Forensic
Examination of Ink. Journal of Forensic Sciences, 55(5), 1304-1310.
4. Saferstein, R. (2001). Criminalistics: An Introduction to Forensic
Science (7th ed.). Upper Saddle River, New Jersy: Prentice-Hall, Inc.
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