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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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Current Graduate Students

Ion-Molecule Interactions in an Ion-Trap Mass Spectrometer for the Characterization of Explosives and Ignitable Liquid Residues

By: Jeannette Perr, Ph.D. in Chemistry Student

The objective of my research will involve studying ion-molecule interactions within the ion trap detector in order to identify and characterize explosive residues and pyrolysis products found in scene debris from other possible ignitable liquid residues while optimizing the conditions for this set of forensically interesting analytes. Prior to trapping the fragments and molecular ions that result from the sample, I will study the effects of three different ionization sources: electron impact ionization (EI), chemical ionization (CI), and glow discharge (GD). There are two main sample sources I will be concentrating on: high explosives that might be found in post-blast debris or environmental contamination of storage facilities and ignitable liquid residue that might be found in fire debris.

High explosives can be thermally labile and not amenable to EI requiring the exploration of softer, gentler ionization methods, such as CI and GD. At some point in the future I will begin work on constructing a RF GD ionization source to be placed on the front end of the ion trap. RF GD ionization sources are currently not in a stage of commercial production.

Ion mobility spectrometry (IMS) is the most common instrument used in the field today to presumptively identify drugs of abuse and explosives. These instruments are typically found in airports where they are used to detect these substances on luggage after swabbing the item. IMS is an analytical technique that distinguishes ionic species based on their reduced mobilities. It is a highly sensitive technique for the detection of trace organics, such as drugs of abuse, under atmospheric pressure conditions. Ion mobility spectroscopy affords a low cost, rapid, and portable method for analysis of organic materials. It is often used for analysis of drugs of abuse by many government agencies. Unfortunately, IMS is not a very selective technique and many substances can interfere with the presumptive identification of a sample. Another aspect of my project will be developing a system that can be used in the field to sniff for explosives that is better then IMS.

The third aspect of my project will be to examine the extraction of explosive residues and pyrolysis products found in scene debris from other possible ignitable liquid residues. Some of the techniques of interest are charcoal strip headspace extraction and solid phase micro extraction (SPME).

Scientific Papers, Book Chapters And Other Publications

  • J. M. Perr, K. G. Furton, and J. R. Almirall, Chemical Ionization Tandem Mass Spectrometry (CI/MS/MS) of Organic Explosives, Talanta, submitted 2004
  • J. M. Perr, K. G. Furton, and J. R. Almirall, Solid Phase MicroExtraction Ion Mobility Spectrometer Interface for Explosives and Taggant Detection, Separation Sciences, 2004, in press.
  • J.R. Almirall and J. Perr, New developments and quality assurance in fire debris analysis, in Analysis and Interpretation of Fire Scene Evidence, J.R. Almirall and K.G. Furton, Eds. CRC Press, 2004, 229-254.  
  • J.R. Almirall and J. Perr, The use of compound specific MS/MS for the identification of ignitable liquid residues in fire debris analysis”, in Advances in Forensic Applications of Mass Spectrometry, J. Yinon, Ed., CRC Press, 2003, 181-230.
  • J.R. Almirall, T. Trejos, A. Hobbs, J. Perr and K.G. Furton, Mass Spectrometry in Forensic Science, in Advances in Mass Spectrometry, Vol 16, A.E. Ashcroft, G. Breton and J.J. Monaghan, Eds., Elsevier, 2004, 167-187.

Oral Presentations At Scientific Meetings

  • "Rapid Screening of Hair Samples Using Solid Phase Extraction and Ion Mobility Spectroscopy"
  • 2001 Pittsburgh Conference and Exposition on Analytical Chemistry and Applied Spectroscopy, presenting author
  • "Characterization of Drugs of Abuse by Ion Mobility Spectrometry and GC/MS"
  • 2000 American Chemical Society, co-author
  • "One Interference Filter, One Silicone Oil, and a Lot of Glass: Glass Refractive Index Database"
  • 2000 American Academy of Forensic Sciences, co-author, 1999 Mid Western Association of Forensic Scientists, presenting author
  • A Comprehensive Approach to Determine the Absolute Detection Limit for Organic Compounds in a Standard Accelerant Mixture Between GC/MS and GC/MS/MSä, 2002 American Academy of Forensic Scientists

Awards:

  • American Institute of Chemists Award
  • 3rd place in Graduate Student Association Scholarly Forum
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Quantitation of Gamma-hydroxybutyric Acid and Gamma-butyrolactone using Capillary Electrophoresis and High Performance Liquid Chromatography

By: Agnes D. Garcia, M.S. in Forensic Science Student

The objective of this project is to develop a rapid analytical method for the screening and quantitation of gamma-hydroxybutyrate (GHB) and gamma-butyrolactone (GBL) and to overcome inherent difficulties with other instrumental techniques.

In recent years there has been an increase in the illicit manufacture of GHB, for the purpose of being sold in the clandestine market.  Possession of GHB has been recently scheduled as a federal offense and is commonly abused as a recreational drug in rave clubs.  It is a depressant with euphoric and hallucinatory effects, and is often abused in conjunction with other illicit controlled substances.

Instrumental analysis of aqueous solutions containing gamma-hydroxybutyrate (GHB), a Schedule I drug, presents difficulties due to its equilibrium with its precursor, gamma-butyrolactone (GBL).  Further, GHB easily undergoes esterification, converting to the butyrolactone in the presence of small amounts of acid.  Gas chromatography, a commonly employed instrument used for quantitation, can convert GHB to the lactone due to thermal reactions in a heated injection port.  The use of a high performance liquid chromatography  (HPLC) or capillary electrophoresis (CE) method and associated instrumentation overcomes thermal degradations  which are prevalent with gas chromatographic methods.  In this study, analysis of  GHB and its lactone was achieved via  HPLC and CE.

A capillary electrophoresis was utilized, equipped  with a fused silica capillary column using an electrokinetic system.  Reversed phase HPLC was also investigated using a complete aqueous HPLC system. Linearity, accuracy, and reproducibility studies are presented.  The effects of organic modifier type, organic modifier concentration, temperature, and voltage on the separation GHB and GBL are also presented.

I officially began the Master of Science in Forensic Science program at FIU in the Fall of 2000 but I have been collaborating with Dr. Almirallâs group since Sept. 1999 and I have taken courses at FIU since Sept. 1999.

Poster and oral Presentations At Scientific Meetings

1999:

  • Garcia, A.D., Shannon, M., Almirall, J.R. Fast Analysis of Gamma-Hydroxybutyric Acid (GHB) by In-Situ Derivatization on an SPME Fiber  oral presentation at the American Academy of Forensic Sciences Meeting, February 1999.
  • 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.
  • Garcia, A.D. and Lurie I. Simultaneous Chiral Determination and Quantitation of Methamphetamine and Related Compounds Using Capillary Electrophoresis oral presentation at the International Association of Forensic Sciences Meeting, August 1999.
  • Garcia, A.D. and Almirall, J.R. Quantitative Analysis of Psilocybin and Psilocin from the Psilocybe Cyanescens (Wakefield) Mushroom by CE poster presentation at the International Association of Forensic Sciences Meeting, August 1999.

2000:

  • Garcia, A.D., Lurie I. Quantitation of 3,4-Methylenedioxymethamphetamine and Related Compounds using Capillary Electrophoresis  oral presentation at the American Academy of Forensic Sciences Meeting, February 2000.
  • Garcia, A.D., Almirall, J.R., Lurie, I. A Comprehensive Review of the Analysis of Controlled Substances by Capillary Electrophoresis, Using Free Zone, MECC, and Cyclodextrin Systems poster presentation at the American Academy of Forensic Sciences Meeting, February 2000. 
  • Almirall, J.R. and Garcia, A.D. Quantitative Analysis of Common Benzodiazepines by Free Zone Electrophoresis poster presentation at the American Academy of Forensic Sciences Meeting, February 2000. 
  • Lurie, I., et al. Use of Dynamically Coated Capillaries for the Routine Analysis of Methamphetamine, Amphetamine, MDA, MDMA, MDEA, and Cocaine using Capillary Electrophoresis oral presentation at the American Academy of Forensic Sciences Meeting, February 2000.
  • Garcia, A. Analytical profile of GHB oral presentation at the Southern Association of Forensic Sciences Meeting, April 2000.
  • Garcia, A. Rise of GHB oral presentation at Club Drugs Conference, August 2000.
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Elemental analysis of biological matrices using a High Resolution- Sector Field Inductively Coupled Plasma Mass Spectrometer (HR-SF-ICP-MS)

By: Waleska Castro, Ph.D. in Chemistry Student

This project aims to develop an analytical method for the analysis of biological matrices such as bones, teeth, plant material, hair, and nails using elemental composition as source of discrimination. Due to the complexity of these matrices, the use of an instrument capable of resolving polyatomic interferences produced during the ionization process with enough sensitivity is required. The ICP-MS technique has already shown to be a great discrimination tool for the analysis of glass and paint matrices. The HR-SF-ICP-MS has the characteristics required for elemental analysis of these complex matrices which are of great interest in forensic field. The development of this method could lead to implementing such a powerful technique in routinely forensic casework involving biological matrices.

Presentations and publications:

  • Annual American Academy of Forensic Sciences Meeting
  • 2005 – Poster: “LIBS: A new tool for elemental analysis of materials in forensic science” (Presenting Author)
  • 2006 – Poster: “Elemental analysis of bone and hair by ICP-MS and LA-ICP-MS” (Presenting Author)
  • Euro Mediterranean Symposium on Laser-Induced Breakdown Spectroscopy (Sep 6-9, 2005-Aachem, Germany)
  • Poster: “Forensic Elemental Analysis of Glass by Laser Induced Breakdown Spectroscopy (LIBS)”
  • 2006 Winter Conference on Plasma Spectrochemistry (January 8-14, 2006 - Tucson, AZ)
  • Poster: “57Fe and 56Fe Limits of detection in glass by HR-ICP-MS and DRC-ICP-MS” (Presenting Author)
  • 8th European Workshop of Laser Ablation in Elemental Analysis (July 19-21, 2006- Zuirch, Switzerland)
  • Poster: “Elemental analysis of biological matrices using LA-ICP-MS for sourcing” (Presenting Author)
  • Federation of Analytical Chemistry and Spectroscopy Societies Annual Meeting (September 25-28, 2006-Lake Buena Vista, FL)
  • Oral Presentation: “Elemental analysis of biological matrices using LA-ICP-MS for sourcing” (Presenting Author)
  • NITECRIME Report from FIU- Bone experiments (Principal Author)
  • Plant Material Analysis Report- “Solution based and laser ablation analyses of plant material using high resolution inductively coupled plasma mass spectrometry (HR-ICP-MS)” (Principal Author)
  • Paper (in preparation): “Capabilities of High Resolution Sector Field Inductively Coupled Mass Spectrometry (HR-SF-ICP-MS) and Dynamic Reaction Cell Inductively Coupled Mass Spectrometry (DRC-ICP-MS) for the forensic analysis of iron in glass samples” (Principal Author)
  • Almirall, Jose R.; Umpierrez, Sayuri; Castro, Waleska; Gornushkin, Igor; Winefordner, James. Forensic elemental analysis of materials by laser induced breakdown spectroscopy (LIBS). Proceedings of SPIE-The International Society for Optical Engineering (2005), 5778 (Pt. 2, Sensors, and Command, Control, Communications, and Intelligence (C3I) Technologies for Homeland Defense IV), 657-666.
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Elemental Charaterization of Paint Samples

By: Joseph Gagnon, M.S. in Forensic Science Student

Quantitative analysis of trace metals in materials by Laser Ablation Inductively Coupled Plasma Mass-Spectrometry (LA-ICP-MS) without the need for matrix-matched standards

By: Sayuri Umpierrez, M.S. in Chemistry Student

The principal aim of this research is the development, optimization and validation of a LA-ICP-MS method that does not require matrix-matched standards so it can be applied to the quantitative analysis of any solid material. This consists of an addition experiment that uses a calibration solution of known concentration of each element to produce a constant background signal, so the spike generated by the ablation signal of the sample can be measured in certain amount of time.

The usefulness of this LA-ICP-MS without matrix-matched standards method for glass and paint analysis will be evaluated in terms of precision, reproducibility, accuracy, limits of detection, and discrimination power. This evaluation will be based on a direct comparison of the new method results from some sets of samples with the previously validated LA-ICP-MS that utilizes internal and external standards for calibration.

Besides, the comparison of two laser systems: LSX-200 plus and New Wave UP213 has been carried out in order to determine the best one for the experiments. Since the New Wave Laser ablates at a shorter wavelength (213 nm), its higher energy allows a better interaction with the sample. Therefore, the New Wave Laser gives better limits of detection and precision (RSD < 5%) due to its increased power compared to the Cetac LSX-200 plus. The crater that results from the New Wave Laser looks like a perfect cylinder while the crater resulting from using the Cetac LSX-200 plus is conical. This difference in the shape of the crater is translated into a different amount of material being removed from the sample. In the case of the Cetac LSX-200 plus, the conical crater produced probably due to less uniform energy distribution along the focus of the sample during the ablation  causes lower signal reproducibility.

Oral Presentations At Scientific Meetings

  • “Análisis Forense de vidrio por SEM-EDS, XRF, LIBS y LA-ICP-MS”. Sayuri Umpierrez, B.S. y Dr. Almirall. I Congreso de Ciencias Forenses en Costa Rica, Nov. 2004

Poster Presentations At Scientific Meetings

  • “Forensic Elemental Analysis of Glass by Laser Induced Breakdown Spectroscopy (LIBS), Laser Ablation Inductively Coupled Plasma Mass Spectrometry, and X-Ray Fluorescence”. Sayuri Umpierrez, B.S., Stephannie Thacker, B.S., Scott Ryland B.S.,  and José R. Almirall, Ph.D. Joint Meeting of the SAFS, MAFS, MAAFS and the CSFS in Orlando, Sept. 2004
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The use of Ion Mobility Spectrometry (IMS) for the detection of drugs and explosives

By: Nicole Manley,  M.S. in Forensic Science Student

Narcotics use and abuse is a major issue and contributes to many societal problems.  The detection and identification of illicit drugs is of major interest in current research.  The objective of this project is to comprehensively evaluate and validate GE Ion Track’s EntryScan3 portal.  The EntryScan3 (ES3) from General Electric (GE) is a new walk-through particle detection portal that rapidly examines individuals for concealed narcotics in a non-intrusive manner with the use of an Ion Mobility Spectrometer (IMS).  Through this research scientific data will be collected from an objective source with the availability of multiple resources.

Controlled experiments with known quantities of cocaine and heroin will be designed to test the capabilities of the instrument.  The limits of detection given by GE, 5ng for both forms of cocaine and 25ng for heroin, will be examined under controlled laboratory conditions.  Five different fabric surfaces located at five different regions of the body will be tested for detection.

In addition to the controlled experiments with known quantities of drugs, experiments also will include the detection of concealed drugs as they are packaged in real cases.  A law enforcement agency will participate in an experiment involving real drugs and with packaging typically used in the illicit market of controlled substances.

Experiments will also be designed to test the instruments selectivity by assessing false positives and false negatives.  Fifteen commonly encountered substances ranging from water and coffee to commonly carried legal drugs will be tested.

A comparative sensitivity study will also be conducted with Ion Track’s next generation Itemiser 2.

Research will also be conducted to determine if the ES3 is capable of alerting for THC.  The instrument is calibrated to detect the active ingredient in cannabis sativa L. and this compound has a low vapor pressure, unlikely to be detected by IMS in the portal.  The detection of the odor signatures of cannabis will be carried out with the use of Solid Phase Micro Extraction (SPME) and gas chromatography/mass spectrometry (GC/MS).

Oral Presentations At Scientific Meetings

  • Southern Association of Forensic Scientists Fall 2004 Joint Meeting, Orlando, Florida, September 20-23, 2004.  “Narcotic Detection By The EntryScan3 Using Ion Mobility Spectrometry (IMS)” N. Manley and J. Almirall.
  • The 80th Florida Annual Meeting and Exposition (FAME), Orlando, Florida, May 6-8, 2004. “Narcotic Detection By The EntryScan3 Using Ion Mobility Spectrometry (IMS)” N. Manley and J. Almirall.
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Use of multiplexed microsatellite markers in Cannabis sativa for genetic fingerprinting

By: Heather Erek, M.S. in Forensic Science Student

Cannabis sativa (marijuana) is the most commonly abused drug in the United States.  There is an increasing need for the development of a method to track the sale and distribution of cannabis plants in the United States.  It is routinely identified in laboratories by using microscopic examination and chemical tests.  However these methods only identify the plant as C. sativa.  A genetic test could demonstrate individuals and clones and associate these clones to a source.  The most common method of human genetic identification is through the use of short Tandem Repeats (STRs).  This method can also be applied to the Cannabis sativa plant.  There are many single reaction STR primers to use for the identification of C. sativa.  The aim of this project is to combine primers into a multiplex for quick and thorough identification of recovered plants. To multiplex the primers many parameters will need to be optimized, including PCR reaction mix, thermal cycling parameters and electrophoresis protocols.  This task will be achieved by combining primers that provide high sensitivity, good reproducibility and a high power of discrimination.

Poster Presentations At Scientific Meetings

  • Almirall, J., Erek, H., Al-Ghanim, H., Development and Use of Microsatellite Markers in Cannabis sativa for Fingerprinting and Genetic Relatedness Analyses, 17th International Symposium on the Forensic Sciences, March 2004.
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Improved Sampling, Pre-Concentration, Detection, and Identification of Hidden Explosives and Illicit Drugs by a Novel Solid Phase MicroExtraction Geometry Coupled with Ion Mobility Spectrometry

By: Patricia Guerra, Ph.D. in Chemistry Student

Ion Mobility Spectrometers (IMS) maintain a considerable presence in airport checkpoints and ports-of-entry for the detection of drugs and explosives. Reaching the full potential of field-portable IMS for effectively detecting these compounds at trace levels is hindered because the sampling technique relies on contact with particles. Ongoing research involves converting commercially available IMS instruments from particle samplers into vapor samplers for the detection of that are available in the headspace of the compounds of interest, explosives and illicit drugs. These volatile chemical markers have significantly higher vapor pressures than their parent compounds and can be sampled, pre-concentrated, and extracted using Solid Phase MicroExtraction (SPME) for subsequent analysis and detection by IMS. The aims of the work include developing a novel SPME geometry for interfacing to an IMS which increases the surface area and extraction efficiency, through modifications in phase chemistry, of the analytes of interest.

Poster Presentations At Scientific Meetings

  • 2007 “A novel solid phase microextraction geometry for explosives detection by ion mobility spectrometry” (poster presentation) 2007 Nanoelectronic Devices for Defense and Security (NANO-DDS) Conference, presenting author.
  • 2007 “New SPME coatings for explosives detection by ion mobility spectrometry (IMS)” (poster presentation) American Academy of Forensic Sciences 59th Annual Meeting, presenting author.
  • 2007 “New SPME coatings for explosives detection by ion mobility spectrometry (IMS)” (poster presentation) American Academy of Forensic Sciences 59th Annual Meeting, Young Forensic Scientist Poster Session, presenting author.
  • 2006 “Detection of Explosives Using Volatile and Semi-Volatile Chemical Markers by SPME-IMS” (poster presentation) 15th International Conference on Ion Mobility Spectrometry, presenting author.
  • 2006 “Detection of Explosives Using Volatile and Semi-Volatile Chemical Markers by SPME-IMS” (poster presentation) Explosives Detection Conference sponsored by TSWG (Technical Support Working Group), presenting author.
  • 2006 “Portable Raman Spectroscopy for Narcotics Detection” (poster presentation) American Academy of Forensic Sciences 58th Annual Meeting, Young Forensic Scientist Poster Session, presenting author.
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Drop-on Demand Inkjet technology for the development of calibration standards for use with Ion Mobility Spectrometers

By: Monica L Joshi, Ph.D. Student in Chemistry (Forensic Track)

The main objective of this project is to develop inexpensive, reliable and robust calibration standards for Ion Mobility Spectrometers using microdrop printing technique. The need for such standards arises from the large number of IMS instruments deployed as trace detectors in various high security areas. Currently, the instrument manufacturers provide calibration standards which are qualitative and only serve the purpose of verifying if the instrument is able to detect an analyte. This project aims to develop standards which are quantitative and can verify if the instrument is consistently detecting illicit substances at the limits that the manufacturer sets it to.

Microdrop generating inkjet systems have been used for several applications in microbiology, optics, engineering and physics. Their ability to produce highly repeatable precise drops with the ability to deliver drops with each drop of known concentration makes the technique very attractive for analytical purposes. For this project, the drop-on-demand inkjet printing technique was chosen to deliver known amount of analyte onto a substrate in a liquid medium and vary the amount delivered by varying the number of drops.

In order to develop calibration standards using the technique described above, several different factors have to be considered and optimized. The project involves the study of different substrates and printing parameters. The analytes of interest for detection by IMS and for standards for these instruments include common explosives, drugs of abuse and their odor signatures. The characterization of these analytes on printing will involve the use of other analytical techniques apart from the presumptive identification by the IMS. Analytical techniques such as Gas Chromatography-Mass spectrometry and FT-Raman will be employed to study the characteristics of the printed standards and the printing solutions.

Poster Presentations At Scientific Meetings

  • Detection of Explosives using Volatile and Semi-volatile Chemical Markers, Explosives Detection Conference-TSWG (Technical Support Working Group), June 2006, Miami Florida
  • Detection of Explosives using Volatile and Semi-volatile Chemical Markers, ISIMS Conference, July 2006, Honolulu Hawaii
  • Detection of Drugs of Abuse using Ion Mobility Spectrometry, FACSS 2006, September 2006, Orlando Florida
  • Study of Detection Limits of Odor Signatures of Drugs of Abuse Using SPME GC-MS and SPME-IMS, AAFS 2007, February 2007, San Antonio Texas
  • Comparison of Detection Limits of Ion Mobility Spectrometers utilizing Microdrop Generating Inkjet Printing, Nano-DDS 2007, June 2007, Washington D.C.
  • Determination of Limits of Detection of Drugs and Explosives by Utilizing Microdrop Generating Inkjet Printed Standards, GRC: Detecting illicit substance-Drugs and Explosives 2007, September 2007, Big Sky Montana
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Fabrication and Optimization of Ion Mobility Spectrometry Instrument for the Analysis of Odor Signature Compounds of Explosives and Drugs

By: Hanh Lai, Ph.D. Student in Chemistry (Forensic Track)

The dissertation involves the construction of an Ion Mobility Spectrometry (IMS) instrument designed and configured to detect and recognize parent compounds of explosives and drugs as well as their odor signature compounds that are readily available in the headspace around a target substance. IMS electronic noses are currently programmed to analyze particles (for the most part) and detect the parent compounds of explosives and drugs, not the associated odor signature compounds. Canines can outperform electronic noses because they can detect the volatile active compounds which are in high concentration in the headspace compared to the non-volatile parent compounds. A new IMS instrument design and configuration is needed to better detect these newly identified volatile active compounds. This dissertation proposes to optimize the instrument operating conditions in terms of the ionization, and the drift tube in order to allow for the ions derived from these molecules to be formed and separated before reaching the detector.

Hanh is a second year Kauffman Doctoral Student from the department of chemistry who research project is of entrepreneurial phenomena in the advancement of scientific instruments. Through the support of the Kauffman Fellowship, Hanh is progressing well in her research and was able to present her work at many conferences. Hanh recently attended the Gordon Research Conference, Detection of Illicit Substances in Big Sky, Montana. This conference brings together international influential policy makers and researchers working at the frontiers of science to shape the next generation of detection technologies in the area of homeland security. There, she competed among young scientists from the governments and corporations and won best poster award. Along with her colleagues, Hanh represented FIU and is recognized as highly dedicated and talented graduate student.

Scientific Papers, Book Chapters And Other Publications

  • Hanh Lai, Patricia Guerra, Monica Joshi, Jose Almirall*, Analysis of Volatile Components of Drugs and Explosives by Solid Phase Microextraction-Ion Mobility Spectrometry, Journal of Separation Science, 2007, accepted.

Poster Presentations At Scientific Meetings

  • Jun 2006, TSWG Explosive Detection Conference, Miami, FL, “Detection of Explosives Using Volatile and Semi-Volatile Chemical Markers”
  • Jul 2007, International Society of Ion Mobility Spectrometry, Honolulu, HI, “Detection of Explosives Using Volatile and Semi-Volatile Chemical Markers”
  • Feb 2007, American Academy of Forensic Science, San Antonio, TX, “Systematic Optimization of Instrumental Conditions; Ion Mobility Spectrometry as a Model Device”
  • Sept 2007, Gordon Research Conference: Detection of Illicit Substances, Big Sky, MN, “Ion Mobility Spectrometry; Successful Detection for Odor Signature Compounds of Explosives and Illicit Drugs”
  • Awards:
  • 2006, Kauffman Doctoral Student Assistantship, Eugenio Pino Entrepreneurship Center
  • 2007, 2nd Year Kauffman Doctoral Student Assistantship
  • 2007, Poster Presentation Award, Gordon Research Conference
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Determination of Origin in Cotton Fibers using LA-ICP-MS

By: Jenny M. Gallo, M.S. in Forensic Science Student

The objective of this project it to determine the origin of a cotton fiber based on its elemental analysis using LA-ICP-MS. Raw cotton material samples will be collected from different locations all over the world and analyzed. It is hypothesized that the different elemental ratios based on environmental effects (i.e. bodies of water, soil nutrients, etc) will be an individualizing characteristic of the cotton material.

I am brand new to the program at FIU and Dr. Almirall’s research group as of August 2007; therefore, this project is in its very early stages.

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Elemental Characterization of Materials Using LA-ICP-MS and LIBS

By: Benjamin E Naes, Ph.D. in Chemistry Student

Elemental analysis of various matrices of forensic interest, such as glass and plastic, using laser ablation inductively coupled plasma mass spectrometry (LA-ICP-MS), laser induced breakdown spectroscopy (LIBS), x-ray fluorescence (XRF), and scanning electron microscopy energy dispersive spectroscopy (SEM-EDS). The majority of the research involves the utilization of LA-ICP-MS and LIBS to characterize materials, in order to aid with drawing associations (or discrimination) between evidence suspected of coming from the same source. In addition, the utility and application of the provided analytical techniques is compared in terms of accuracy, precision, detection limits, and discrimination power, ultimately to determine which technique is optimum for a given matrix and/or if two or more techniques combined can provide complimentary information.

Poster and oral Presentations At Scientific Meetings

  • A Comparison Of Nanosecond Vs Femtosecond La-Icp-Ms For The Analysis Of Glass, Benjamin Naes*, Jhanis Gonzalez, Richard Russo, and Jose Almirall [poster presentation, Winter Plasma Conference on Spectrochemistry, 2006]
  • 57fe And 56fe Limits Of Detection In Glass By Hr-Icp-Ms And Drc-Icp-Ms, Waleska Castro*, Tatiana Trejos, Benjamin Naes and José Almirall [co-author, poster presentation, Winter Plasma Conference on Spectrochemistry, 2006]
  • Elemental Analysis Of Glass By La-Icp-Ms, A Comparison Of Various Laser Methods To Optimize Sensitivity, Precision, And Accruracy, Benjamin Naes*, Jhanis Gonzalez, Richard Russo, and Jose Almirall [oral presentation, American Academy of Forensic Science, 2006]
  • Elemental Analysis Of Bone And Hair By Icp-Ms And La-Icp-Ms, Waleska Castro*, Benjamin Naes, Tatiana Trejos, and José Almirall [co-author, poster presentation, American Academy of Forensic Science, 2006]
  • Micro-Homogeneity Studies Of Trace Elements In Solid Matrices By La-Icp-Ms: Implications For Forensic Comparisons, Tatiana Trejos, Benjamin Naes and José Almirall [co-author, oral presentation, American Academy of Forensic Science, 2007]
  • Comparison Of Femtosecond Vs Nanosecond Laser Ablation Sampling Coupled To Icp-Ms For The Analysis Of Glass And Other Matrices Of Interest To Forensic Scientists, Benjamin Naes*, Jhanis Gonzalez, Richard Russo, and Jose Almirall [poster presentation, American Academy of Forensic Science, 2007]
  • Forensic Analysis Of Glass By Libs, A Comparison To Xrf And La-Icp-Ms For Elemental Profiling, Benjamin Naes*, Jhanis Gonzalez, Richard Russo, and Jose Almirall [oral presentation, American Academy of Forensic Science, 2007]
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