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DEPARTMENT OF CHEMISTRY AND BIOCHEMISTRY AND INTERNATIONAL FORENSIC RESEARCH INSTITUTE
Florida International University, University Park, Miami, Florida 33199


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Former Graduate Students

Elemental Analysis of Automotive Paint Samples by Laser Ablation-Inductively Coupled Plasma-Mass Spectrometry (LA-ICP-MS) and Paint and Glass by Laser Induced Breakdown Spectroscopy (LIBS)

By: Andria Hobbs, Master of Science in Forensic Science (Awarded 2003)

Glass and paints are frequently encountered forms of evidence submitted to forensic laboratories.  This study has developed methods to complement commonly used techniques in a crime laboratory to better characterize these evidence materials for forensic purposes.  Automotive paint samples have been analyzed by LA-ICP-MS to determine the discrimination power of the technique.  Optimization and validation studies were first conducted, including a homogeneity study.  Automotive paints indistinguishable by common methods have been analyzed in order to determine the forensic utility of LA-ICP-MS and have shown that LA-ICP-MS can distinguish between those samples.  Additionally, household paint samples known to contain high levels of lead were analyzed by the developed LIBS technique.  For glass samples, LIBS was able to classify the glass by type and to further distinguish 51% of the containers.  These techniques are now available for forensic scientists for the analysis of automotive paint samples and glass samples.

Oral Presentations At Scientific Meetings

  • AAFS 56th Annual Meeting, Dallas, TX., February 2004, “Improved Discrimination of Automotive Paints through LA-ICP-MS” A. Hobbs, T. Trejos, and J. Almirall.*
  • SPIE's 17th Annual International Symposium on Aerospace/Defense Sensing, Simulation, and Controls, Orlando, FL. “Trace Elemental Analysis of Glass and Paint Samples of Forensic Interest by ICP-MS Using Laser Ablation Solid Sample Introduction” J.R. Almirall, T. Trejos, A. Hobbs, and K. Furton.
  • AAFS 55th Annual Meeting, Chicago, IL., February 2003, “Comparison of the Elemental Profiling Techniques of LA-ICP-MS and LIBS for Forensic Automotive Paint Samples” A. Hobbs and J. Almirall.*
  • FACSS 29th Annual Meeting, Providence, Rhode Island. “Optimization of Ablation Parameters for the Elemental Profiling of Automotive Glass and Paints by LA-ICP-MS and LIBS” A. Hobbs, S. Montero, T. Trejos, and J. Almirall.*
  • ENSFI 8th Working Group Meeting, Madrid, Spain. “Elemental Analysis of Glass and Paint by ICP-MS, ID-ICP-MS, and LA-ICP-MS”. J. Almirall, T. Trejos, S. Montero, and A. Hobbs.
  • IAFS 16th Triennial Meeting, Montpellier, France. “Trace Elemental Profiling of Automotive Paints by Laser Ablation- Inductively Coupled Plasma- Mass Spectrometry” A. Hobbs and J. Almirall.*
  • ACS 223rd National Meeting, Orlando, Florida. “Sample introduction of materials of forensic interest using laser ablation for inductively coupled plasma mass spectrometry analysis of metals” S. Montero, J. Almirall, A. Hobbs, T. Trejos, L. Morris, S. Gross.
  • AAFS 54th Annual Meeting, Atlanta, Georgia, February 11-16, 2002. “Elemental Profiling of glass fragments by ICP-MS as evidence of association: analysis of a case” S. Montero, A. Hobbs, T. French, J. Almirall.*

* Presenting author

Scientific Papers, Book Chapters And Other Publications

  • J.R. Almirall, T. Trejos, A. Hobbs and S. Montero, Significance of elemental analysis comparisons for a wide variety of glass samples using ICP-MS; Description and use of a database, Journal of Forensic Science, in preparation.
  • A. Hobbs and J.R. Almirall, Laser Induced Breakdown Spectroscopy (LIBS) in forensic analysis of glass and paint samples, Forensic Science International, in preparation.
  • J. Almirall, T. Trejos, A. Hobbs, Jeannette Perr and K. Furton. Mass spectrometry in forensic science, Advances in Mass Spectrometry, 2004, 16: 167-187.
  • E. Livengood, A. Hobbs, and J.R. Almirall, A comparative analysis of GRIM2 and GRIM3 for refractive index measurements, Science and Justice; Journal of the Forensic Science Society, submitted 2003.
  • J.R. Almirall, T. Trejos, A. Hobbs and K.G. Furton, Trace elemental analysis of glass and paint samples of forensic interest by ICP-MS using laser ablation solid sample introduction, in Sensors, and Command, Control, Communications, and Intelligence Technologies for Homeland Defense and Law Enforcement (5071), E.M. Carapezza, Ed., Proceedings of the SPIE - The International Society for Optical Engineering, 2003, 193-204.
  • A. Hobbs and J.R. Almirall, Trace elemental analysis of automotive paints by laser ablation inductively coupled plasma mass spectrometry (LA-ICP-MS), Journal of Analytical and Bioanalytical Chemistry, 2003, 376: 1265-1271.
  • S. Montero, A. Hobbs, T. French and J.R. Almirall, Elemental profiling of glass fragments by ICP-MS as evidence of association: analysis of a case”, Journal of Forensic Sciences, 2003, 48(5) 1101-1107.
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Identification of Gamma-HydroxyButyrate (GHB) and
Gamma-Hydroxybutyrolactone (GBL) in aqueous samples

By: Jodi Meyers, Master of Science in Forensic Science (Awarded 2003)

Gamma-HydroxyButyrate (GHB) is an inhibitory neurotransmitter with euphoric, hallucinatory and sedative effects.  In recent years there has been an increase in the abuse of this drug which has led to a demand for analytical methods of GHB.  GHB, also known as the ãdate rapeä drug, has received much media attention for its abuse as a strong sedative which is being placed in the drinks of unknowing victims at bars.

In aqueous solutions GHB exists in equilibrium with its lactone, GBL (Gamma-Hydroxybutyrolactone).  This research will include a study of the equilibrium reached between GHB and its corresponding lactone under acidic and basic conditions.  Equilibrium ratios for solutions of GHB and GBL buffered at various pHs and maintained in different temperature environments will be determined over time using    1H NMR.  Further study of current methods of GHB detection will be investigated to optimize parameters and determine detection limits.  Specifically, a SPME on-fiber derivatization method followed by GC-MS analysis will be developed and optimized for detection of GHB and its analogues.

Scientific Papers, Book Chapters And Other Publications

  • Meyers JE, Almirall JR. A study of the effectiveness of commercially available drink coasters for the detection of ‘date rape’ drugs in beverages. J. Analyt. Tox.,Volume 28, Issue 8, November/December 2004, pp.685-689.
  • Meyers JE, Almirall JR.  Analysis of gamma-hydroxybutyric acid (GHB) in spiked water and beverage samples using solid phase microextraction (SPME) on-fiber derivatization/ gas chromatography-mass spectrometry (GC/MS).  Accepted to the Journal of Forensic Science 2003.

Oral Presentations At Scientific Meetings

  • 2003 American Chemical Society Florida Annual Meeting and Exhibit, Orlando, Florida, presenting author.  “A Study of the Effectiveness of Coasters in Detecting the Presence of Illicit Date Rape Drugs in Beverages.”  Jodi E. Meyers*, and José Almirall.
  • 2003 American Academy of Forensic Sciences, Chicago, Illinois, presenting author.  “The Analysis of gamma-Hydroxybutyric Acid (GHB) and gamma-Butyrolactone (GBL) in Forensic Samples Using GC/MS and 1H NMR.”  Jodi E. Meyers*, and José Almirall.
  • ACS 223rd National Meeting, Orlando, Florida, April 7-11.  “SPME on-fiber derivatization of Gamma-Hydroxybutyric Acid (GHB) in Forensic Analysis.”  Jodi E. Meyers*, Gigi Galiani, Agnes Garcia, José Almirall.

Awards

  • ACS Analytical Chemistry award (2000)
  • MBRS Rise Scholarship (2002)
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Development of Microsatellite Loci in Cannabis Sativa L.

By: Hussain AlGhanim, Master of Science in Forensic Science (Awarded 2003)

Microsatellite DNA or simple sequence repeat (SSR) provide an ideal tool for assessing the genetic diversity of plants due to their high information content, ease of genotyping, codominant and multiallelic nature, high discriminatory power, and reproducibility.  Microsatellites have been used successfully in agricultural and breeding studies as well as in the analysis of natural population.

Microsatellites are DNA sequences of four or fewer bases that are repeated in tandem arrays (i.e. ATATATATATATATATATAT).  Such microsatellite sequences have been found randomly distributed throughout the genomes of all eukaryotes assayed except yeast.  The highly polymorphic microsatellites have proved very useful in population genetics studies.

This proposed work specifically aims to identify a number of microsatellite loci capable of capturing polymorphism among different Cannabis individuals. The microsatellite loci will be searched for in a systematic effort by marker enrichment technique, which consists of: 1) screening the extracted DNA of Cannabis sativa L. with specific repeat unit probes, 2) sequencing the positive clones, and 3) designing oligonucleotide primers on either side of the repeat region.

It is felt that this information can be used to track marijuana growers and distribution networks as well as confirm (through comparisons akin to human DNA comparisons) the source of origin of individual plants. Therefore, this technique could be used by operational laboratories that have an interest in tracking marijuana sources through genetic data.

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Elemental Analysis of Forensic Glass by ICP-MS

By: Shirly Montero, Ph.D.(Awarded 2002)

The value of glass evidence in forensic investigations has been well established in a number of studies and publications. Measurements of physical and optical characteristics are widely used to compare recovered pieces to a known source. However, improvements in glass quality control limit their discriminating power and have led to a need for the development of instrumental techniques for the elemental analysis of glass fragments that provide better discrimination between specimens.

This project addresses the optimization, standardization and validation of a method for the analysis of small glass samples (~ 2 mg) by ICP-MS using external calibration and isotope dilution experiments. Later on, we will also introduce laser ablation LA-ICP-MS for the analysis of glass using isotope ratios. The limitations of the instrumental techniques and the sample preparation protocols, including challenges in the dissolution of the glass or uniformity of the sample, are to be evaluated. A representative set of glasses (~1000) from a variety of sources will be analyzed by these methods to determine the informing power of elemental analysis determinations from glass specimens.

I began in the Ph.D in Chemistry program in the Spring of 1999. In the summer of 1999 I was a graduate student guest at Oak Ridge National Laboratory, Chemical and Analytical Science Division, Analytical Spectroscopy Section. Inorganic Mass Spectrometry Group.  I began my research in the Fall of 1999.

Scientific Papers, Book Chapters And Other Publications

  • S. Montero,  A. L. Hobbs,  T. A. French,  J. R. Almirall. “Elemental Profiling of Glass Fragments by ICP-MS as Evidence of Association: Analysis of a Case” J Forens Sci , 2003, 48 (5), 1101-7.
  • T. Trejos,S. Montero, J.R. Almirall. “Analysis and Comparison of Glass Fragments by Laser Ablation Inductively Coupled Plasma Mass Spectrometry (LA-ICP-MS) and ICP-MS” Anal Bioanal Chem, 2003, 376, 1255-64.
  • D.C. Duckworth, S.J. Morton, C.K. Bayne, S. Montero, R.D. Koons and J.R. Almirall, "Forensic Glass Analysis by ICP-MS: A Multi-Element Assessment of Discriminating Power Via Analysis of Variance and Pair-Wise Comparisons", J. Anal. At. Spectrom., 2002, 17, 662-8.
  • D.C. Duckworth, S.J. Morton, C.K. Bayne, S. Montero, and J.R. Almirall, "ICP-MS and ID-ICP-MS Methods for the Analysis of Forensic Glass", in Proceedings of the 49th ASMS Conference on Mass Spectrometry and Allied Topics, Chicago, Illinois, May 27-31, 2001.

Conferences, Workshops and Presentations

  • 2002 IAFS 16th Meeting, Montpellier, France, September 2-7. “Elemental analysis of glass fragments by inductively coupled plasma mass spectrometry (ICP-MS) and laser ablation ICP-MS (LA-ICP-MS)” S. Montero, A. Hobbs, T. Trejos, J.R. Almirall2002 6th European Laser Ablation ICP-MS Workshop. Utrecht, Netherlands, 24-25 June. “ICP-MS, ID-ICP-MS and LA-ICP-MS methods for the analysis of forensic glass” S. Montero, J.R. Almirall
  • 2002 ACS 223rd National Meeting, Orlando, Florida, April 7-11. “Sample introduction of materials of forensic interest using laser ablation for inductively coupled plasma mass spectrometry analysis of metals” S. Montero, J. Almirall, A. Hobbs, L. Morris, S.Gross
    2002 SPIE 16th Annual International Symposium, Orlando, Florida, April 1-5. “Associations of glass fragments by their trace elemental content using ICP-MS and LA-ICP-MS in the analysis scheme” J.Almirall, S. Montero, K. Furton
  • 2002 AAFS 54th Annual Meeting, Atlanta, Georgia, February 11-16. “Elemental Profiling of glass fragments by ICP-MS as evidence of association: analysis of a case” S. Montero, A. Hobbs, T. French, J. Almirall
  • 2001ASMS 49th  Annual Conference, Chicago, Illinois, May 27-31. “ICP-MS and ID-ICP-MS Methods for the analysis of forensic glass”  S. Montero, J. Almirall, D. Duckworth, C. Bayne
  • 200 AAFS 53rd Annual Meeting, Seattle, Washington, February 19-24. “Method validation studies for glass comparisons using elemental data from ICP-MS and ID-ICP-MS” S. Montero, D. Duckworth, C. Bayne, R. Koons, J. Almirall
  • 2000 FACSS 2000, Nashville, Tennessee, September 24-28. “Relative discriminating power of refractive index, ICP/AES, and ICP/MS for forensic glass comparisons” D. Duckworth, C. Bayne, S. Montero, J. Almirall, R. Koons
  • 2000 FAME 2000, Orlando, Florida. “Trace elemental analysis of forensic glass by ICP-MS” S. Montero, K. Furton, J. Almirall , D. Duckworth, S. Morton, C. Bayne, R. Koons
  • 2000 ACS 219th National Meeting, San Francisco, California, March 26-30. “Trace elemental analysis of forensic glass samples by ICP-MS” J. Almirall, K. Furton, D. Duckworth, S. Morton, C. Bayne, S. Montero
  • 2000 AAFS 52nd Annual Meeting, Reno, Nevada, February 21-26. “Advances in Elemental Analysis of Glass by ICP-MS” S. Montero, K. Furton, D. Duckworth, S. Morton, C. Bayne, R. Koons, J. Almirall
  • 2000 AAFS 52nd Annual Meeting, Reno, Nevada, February 21-26. “Improved Sensitivity and Selectivity for the Detection and Identification of Ignitable Liquid Residues from Fire Debris by Ion Trap Mass Spectrometry” M. Plasencia, S.Montero, J. Krivis, A. Amstrong, J. Almirall
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Constructing a database for Cannabis sativa L.
Using Amplified Fragment Length Polymorphisms

By: Sabrina Frank, Master of Science in Forensic Science (Awarded 2002)

In a collaborative research project between the Institute of Forensic Science at the University of New Haven, Connecticut Forensic Science Laboratory and Florida International University we have decide to focus on a single plant species, Cannabis sativa L., for the development of a molecular strategy for plant DNA typing.  We have selected Cannabis (marijuana) because it is an illegal substance grown across the United States and in other countries.  In addition cannabis is generally accepted as being a single species so botanical identification is not difficult.

The research includes the generation of DNA profiles from different Cannabis sativa L. to populate a database and to determine the genetic diversity present in the sample population. The survey of genetic diversity will result in an Amplified Fragment Length Polymorphism (AFLP) database for marijuana. The database can be used to provide linkage between marijuana growers, distributors and users.  The current technology of AFLP is a DNA typing technique used to generate large numbers of molecular markers for genetic mapping.   The use of AFLP will allow the Forensic Community and Law enforcement to improve there current methods that are being used for DNA typing.   Currently there is not a Cannabis AFLP population databases that exist for comparison with evidentiary profiles.

Poster Presentations At Scientific Meetings:

  • 2002 ACS 221st Mational Meeting, Olrando, Fl." Quantitative Analysis of Cannabis sativa DNA Extracts by Capillary Electrophoresis."  S. Frank,  S. Winkle and J. Almirall
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Characterization of Inks and their Aging Properties

By: Louis Morris, Master of Science in Forensic Science (Awarded 2002)

The purpose of this research was to study the potential of two analytical techniques in distinguishing individual ink samples.  Lines from forty-one (22 black, 19 blue) different pens were written on three types of paper and chemically analyzed.  Thin Layer Chromatography/Laser Induced Fluorescence (TLC/LIF) was used to characterize the organic properties of dyes, while Laser Ablation Inductively Coupled Mass Spectrometry (LA/ICP/MS) examined their trace metal composition.  TLC/LIF could not discriminate twelve out of the forty-one inks using Rf values and band fluorescence.  LA/ICP/MS could not discriminate sixteen out of the forty-one inks using count ratios and relative percentages of selected metals.  Copper was the most abundant element in all forty-one inks, while lead and zinc were the best discriminators.  Seven out of the twenty-two black, and six out of nineteen blue pens could not be discriminated using either method.

I began the Master of Science in Forensic Science in the Spring of 2000 and attended a summer internship at the U.S. Secret Service Laboratory in Washington D.C.  I began my research on inks in the Fall of 2000.

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Forensic Evaluation Of Automotive Lenses

By: Susan T. Gross, Master of Science in Forensic Science (Awarded 2001)

Hit and run type accidents and other vehicle accidents often leave trace evidence behind.  This trace evidence can include small pieces of paint, body fillers, plastic bumper bars, tire rubber and/or plastic lenses.  Due to the lack of background information as to the diversity and physical and chemical properties of plastic lenses, the evidentiary value of this type of evidence is unknown. To generate the discrimination power of automotive lenses, this study proposes to analyze the lenses by five different instrumental techniques.  These techniques will examine both the organic and inorganic composition of these plastic lenses.  The five techniques that will be utilized are:  Pyrolysis Gas Chromatography (PGC), Fourier Transform Infrared Spectroscopy (FTIR), Raman Spectroscopy, Scanning Electron Microscopy - Energy Dispersive X-ray (SEM-EDX), and Laser Ablation Inductively Coupled Plasma - Mass Spectrometry (LA-ICP-MS).   Three of these techniques (PGC, FTIR and SEM-EDX) were chosen for this project since they are commonly found in forensic science laboratories and they characterize materials based on both organic and inorganic content.  Two additional instruments that will be utilized in this project, that may provide additional information, are Raman and LA-ICP-MS.  The informing power of using each of the techniques by itself and the informing power of using the techniques in combination are being researched. Automotive lenses of known origin are being analyzed in triplicate by PGC, FTIR, SEM-EDX, Raman, and LA-ICP-MS.  Various autobody shops and junk yards were contacted to obtain a representative cross-section of automotive lenses that would be expected to be found at a crime scene.  Automotive lenses were obtained from a variety of vehicles of model years 1985 through 2000.  Both American and Foreign cars were included in this diverse sample set.  Quantitative data from all five instrumental techniques will be summarized and evaluated by the method of Smalldon and Brown for the determination and assessment of discrimination power.

I began in the Master's of Forensic Science program in the Fall of 1999.  I began my research in the Spring of 2000.  My research will be presented at the American Academy of Forensic Sciences at the 2001 Meeting in Seattle, Washington , February 19 - 24.

Scientific Papers, Book Chapters And Other Publications

  • S. Gross, J. Wilson, R. Duevel and J.R. Almirall, ãEvaluation of Automotive Lenses for Forensic Applications by FTIR, PGC, Raman, and Laser Ablation ICP-MSä, Journal of Forensic Sciences, 2002, submitted.
  • Gross, S. "Detecting Psychoactive Drugs in the Developmental Stages of Mushrooms". J Forensic Sci 2000; 45(3): 527-537.

Poster and Oral Presentations At Scientific Meetings

  • Gross, S. "Detecting Psychoactive Drugs in Mushrooms" oral presentation at the Midwestern Association of Forensic Scientists Meeting, October 1998.
  • Gross, S., Garcia, A.D., Almirall, J. R. "The Analysis of the Psilocybe Cyanescens (Wakefield) Mushroom"  oral presentation at the American Academy of Forensic Sciences Meeting, February 1999
  • Almirall, J. R., Gross, S., Garcia, A.D., A Comparison of GC-MS, LC-ECD, LC-MS, and CE Methods for the Analysis of the Psilocybe Cyanescens (Wakefield) Mushroom oral presentation at the Pittcon Meeting, March 1999.
  • Gross, S., Garcia, A.D., Almirall, J. R. "The Analysis of the Psilocybe Cyanescens (Wakefield) Mushroom"  poster presentation at the International American Academy of Forensic Sciences Meeting, August 1999.

Awards:

  • New Scientist Award Recipient.  Award presented by Midwestern Association of Forensic Scientists, October 1999.
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Identification and Characterization of Pyrolysis Products in Fire Debris Analysis

By: Eric Stauffer, Master of Science in Forensic Science (Awarded 2001)

The objective of my research is to identify and characterize pyrolysis products found in fire debris in order to distinguish these compounds from possible ignitable liquid residues (ILR).

Pyrolysis products are released by burning substrate during a fire. These products produce a response in a gas chromatograph that can mask the pattern of petroleum distillates, during the analysis of fire debris in a suspected arson case. Different objects and materials commonly encountered in fire debris analysis have been burned under different conditions and their pyrolysis products have been studied.

Common materials considered to be possible sources of pyrolysis products once burned, and found in residential buildings have been classified into four main levels of types of substrates. Level 1 includes materials fixed on the floor, walls and ceiling of a building. Level 2 includes all the furniture and other large items that can be found in a room. Smaller objects found inside or nearby the furniture constitute level 3 type substrates. Finally, level 4 items are categorized as components within larger objects but are present in small quantities and not part of the bulk material of the object for example, the dyes found in carpet fibers. The dyes themselves would classify as level 4 while the polymer material of the carpet would classify as level 1.

Each level is then separated into sublevels according to the class of compounds of the materials and objects found in each level such as polymers from a carpet fiber, wood products from a furniture item, natural fibers from cloth materials, etc.  This classification has been constructed in order to be able to group some target pyrolyzates by both object types and by material (chemical) composition, after burning.

A first study of pyrolysis products has been conducted under controlled heating conditions with a Pyrolyzer-Gas Chromatograph-Mass Spectrometer (CDS AS-2500, HP 6890-HP 5973). By using a pyrolyzer it has been possible to obtain the set of pyrolysis products released by the substrates under specific temperature conditions. Generally, there are only three degradation mechanisms by which the pyrolysis process occurs. The first one is random scission, which is the production of free radicals along the backbone of the polymer. The second is the side group scission, where the backbone loses molecules or atoms attached to it. The final one is monomer reversion in which the polymer returns simply to its monomer. Hence, it has been possible to study these degradation mechanisms and to compare them to the pyrolyzates obtained during the analyses.

Samples have been burned under different conditions and extracted in the same way that ILR are usually extracted from fire debris. Passive headspace extraction using activated charcoal strip and elution with carbon disulfide has been used in this study. Analyses of the resulting extract were conducted with both GC-FID (HP 5890) and GC-MS (Varian 3400cx and Varian 2000).

Resulting chromatograms were compared to the ones obtained by Py-GC/MS in order to estimate the influence of the different burning conditions and the extraction procedure. Then, these have been compared to a collection of ILR standards in order to estimate their interference using peak pattern analysis.

It is possible to construct a classification of the pyrolysis products with respect to the different levels of objects and substrate materials. In addition, it has been possible to estimate some parameters in the burning procedure and in the extraction procedure that influence the presence of pyrolysis products. Finally, It has been possible to show the interference of pyrolysis products with the recovery of ILR.  Furthermore, a comparison of the relative detection limits of gasoline in the presence of pyrolysis products is presented. The effectiveness of using a GC-FID compared to a GC-MS or GC-MS-MS is also presented. These studies show the improved detection and identification of ILR in the presence of pyrolyzates when GC-MS or GC-MS-MS are used over just GC-FID alone.

I began my Master of Science in Forensic Science degree program at FIU and joined the group in the Fall of 1999.

Oral Presentations At Scientific Meetings

  • Participation at the Annual Meeting of the American Academy of Forensic Sciences in Reno, Nevada, 2000.
    "Fire debris analysis by comprehensive two-dimensional gas chromatography", Presented at the Florida International University 2000 Scholarly Forum.
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