Application of Chemometrics and GC-MS Analysis for the Identification of Traces of Ignitable Liquids in Fire Debris Samples:  This research makes use of the chemometric method of target factor analysis to aid the fire debris analyst in detecting and statistically assessing the potential presence of ignitable liquids even at levels below those acceptable for a positive determination under current practices. The method can detect an ignitable liquid even in the presence of high levels of interfering background components resulting from the fire. Current practices in fire debris analysis are based on the ASTM E 1618 protocol, which relies on visual pattern recognition for the detection of the presence of an ignitable liquid.  Pattern recognition becomes more challenging when the contribution of background components is strong and the ignitable liquid residue contribution is weak.  This research is conducted in collaboration with Bureau of Fire Standards and Training in Ocala, FL, and the Bureau of Forensic Fire and Explosives Analysis, Tallahassee, FL.  (National Institute of Justice - Office of Justice Programs, U.S. Department of Justice award 2008-DN-BX-K069) 

Videos: Ocala Burns-

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Implementation of a Searchable Ignitable Liquids Database Tool for the Fire Debris Analysis Community: This research has produced prototype software for the analysis of fire debris.  The software was developed based on previous research at NCFS on the total ion spectrum obtained from GC-MS data sets.  The software compares the total ion spectrum of a fire debris sample to a library of total ion spectra of reference ignitable liquids and substrate materials.  The results rank the reference ignitable liquid spectra from the most similar to the fire debris sample to the least similar.  NCFS is working with forensic laboratories to test the software on casework samples.  (National Institute of Justice - Office of Justice Programs, U.S. Department of Justice award 2008-IJ-CX-K401)

Ignitable Liquids Reference Collection and Database: NCFS maintains an online database of GC-MS data for commercially available ignitable liquids commonly found in fire debris. The data base is produced in collaboration with the Technical Working Group for Fire and Explosions (TWGFEX). The database is accessed free-of-charge by fire debris analysts from around the world as a routine part of their casework. If an analyst needs to obtain a reference sample of a database entry, the sample can be ordered from NCFS at a minimal fee to cover handling and shipping.  (National Institute of Justice - Office of Justice Programs, U.S. Department of Justice award 2008-IJ-CX-K401) ILRC Database

Substrate Database: The Substrate Database was developed by the National Center for Forensic Science in collaboration with the Ignitable Liquids Reference Collection committee of the Technical Working Group for Fire and Explosives (TWGFEX).  The Substrate Database is a compilation of headspace GC/MS data from burned and unburned materials that are common to fire scenes.  These materials may produce compounds that can interfere with the identification of ignitable liquids in fire debris.  The Substrate Database can assist the fire debris analyst by demonstrating the types of compounds and chromatographic patterns that may be produced by these commonly encountered materials.  (National Institute of Justice - Office of Justice Programs, U.S. Department of Justice award 2008-IJ-CX-K401) Substrate Database

Statistical Assessment of the Probability of Correct Identification of Ignitable Liquids in Fire Debris Analysis: NCFS is investigating the use of multiple chemometric methods to identify ignitable liquid residues in fire debris and correctly classify the residue into an appropriate ASTM E1618 – 2006 class.  An emphasis is placed on studies of probabilistic classification models.  (National Institute of Justice - Office of Justice Programs, U.S. Department of Justice award 2009-DN-BX-K227)

Analysis of Peroxide Explosives: This research has examined methods for the analysis of tri acetone tri peroxide (TATP) by various mass spectrometry methods.  The research also focuses on determination of synthetic route and source material identification from trace impurity analysis of TATP samples. Laboratory and field experiments have been conducted and reported in peer-reviewed literature.  (National Institute of Justice - Office of Justice Programs, U.S. Department of Justice award 2006-DN-BX-K009)

Videos: TATP-

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Smokeless Powders Database: The Smokeless Powders Database is being developed by the National Center for Forensic Science in collaboration with the Technical Working Group for Fire and Explosives (TWGFEX).  The Smokeless Powders Database consists of product information, physical description and measurements, and identification of the chemical components of smokeless powders.  The database will be accessible to forensic scientists free-of-charge.  The information and data contained in the database will be a compilation from NCFS and other forensic laboratories.  (National Institute of Justice - Office of Justice Programs, U.S. Department of Justice award 2008-IJ-CX-K401) Smokeless Powder Database

Two Dimensional Correlation Mass Spectrometry: The technique of two dimensional correlation mass spectrometry (2D-CMS) based on collision induced decomposition energy and resonance excitation time perturbations has been applied to the analysis of fragmentation pathways for explosives and explosives-related compounds in an ion trap mass spectrometer. The method holds promise for the development of improved forensic analysis techniques.

LIBS Analysis of Energetic Materials: NCFS, in collaboration with the Townes Laser Institute and Center for Research and Education in Optics and Lasers (CREOL) is investigating the use of Laser Induces Breakdown Spectroscopy (LIBS) for the analysis of organic residues, including explosives.  Emphasis is on the chemometric approaches, standoff detection and plasma fundamentals. (Multidisciplinary university research initiative – MURI, U.S. Army Research Office award W911NF0610446)

Transferable Fiber Census: NCFS is partnering with The West Virginia Forensic Science Initiative (WVU-FSI) to conduct a census of the transferable fiber population across the United States. The census categorized the transferable fiber population based on fiber type and color. Results from the census were analyzed for possible regional and seasonal variations and the data will assist forensic fiber analysts in the interpretation of the statistical significance of fiber trace evidence.  (National Institute of Justice - Office of Justice Programs, U.S. Department of Justice award 2005-MU-MU-K004)

Fiber Dye Analysis: Fiber trace evidence often plays an important role in criminal cases. Individualization of fibers and the discrimination between questioned and known samples is facilitated by the analysis of the fiber dyes. One method is a statistical comparison of the visible absorption spectra of the fiber dyes. Another method is a molecular-level analysis of the fiber dye composition performed by direct infusion electrospray ionization – mass spectrometry (ESI-MS) coupled via an electro spray interface.  (State of Florida Type II Research Center funds)

One method is a statistical comparison of the visible absorption spectra of the fiber dyes.  Another method is a molecular-level analysis of the fiber dye composition performed by direct infusion electrospray ionization – mass spectrometry (ESI-MS) coupled via an electro spray interface.  (State of Florida Type II Research Center funds)
                                                                                                                                  
Identification of Textile Fibers: Dr. Campiglia’s research group focuses on developing nondestructive analytical methodology capable of providing highly discriminating identification of textile fibers encountered as physical evidence in criminal investigations. In addition to the contribution of the textile dye (or dyes) to the fluorescence spectrum of the fiber, we investigate the contribution of intrinsic fluorescence impurities – i.e. impurities imbedded into the fibers during fabrication of garments - as a reproducible source of fiber comparison. The methodology, instrumentation and data analysis we propose is expected to increase the discriminating power of fluorescence microscopy. Because the same approach can be used to track down previous fiber exposure to multiple washings, weathering and cigarette smoke, forensic scientists will have a non-destructive tool to obtain additional information on fiber history.

Glass Analysis by Laser-Induced Breakdown Spectroscopy (LIBS): LIBS potentially offers a relatively inexpensive elemental analysis methodology to facilitate forensic analysis of glass samples. An investigation of the use of 1064 nm nanosecond single pulse LIBS for the analysis of glass and automotive paint samples has been conducted at NCFS.  Sample analysis and discrimination has been performed by various parametric and nonparametric statistical methods.  (National Institute of Justice - Office of Justice Programs, U.S. Department of Justice awards 2004-IJ-CX-K031 and 2006-DN-BX-K251)

Location of Human Remains by a Controlled Biological System: Trained cadaver dogs provide a valuable service to the forensic and law enforcement communities. The dog's evolved sensory system coupled with adaptable on-board data processing is a tough combination to reproduce with mechanical sensor systems; however, other controlled biological systems offer similar capabilities. The Bee Alert program at the University of Montana specialized in the use of bees as a controlled biological system that can be rapidly trained and deployed. UCF is partnering with the Bee Alert program to test the trainability and performance of honey bees in the location of human remains and clandestine laboratories.  (National Institute of Justice Office of Justice Programs, U.S. Department of Justice award 2005-MU-MU-K004)

Analysis of Writing Inks: A study has been conducted of the use of electrospray – mass spectrometry to discriminate between inks from a series of commercial pens.  Inks from three classes of pens (gel, roller ball, and ball point) were analyzed. A high degree of discrimination was obtained within each of the three classes based on the composite results from a set of three mass spectrometry methods. (State of Florida Type II Research Center funds)

Controlled Substances: Dr. Blair’s research group focuses on the development of new presumptive tests for the officer in the field and the laboratory technician of emerging substances of abuse. For example, Benzylpiperazine (BZP, A2, Frenzy, Nemesis) has no distinct presumptive test.  Analysis is limited to GC/MS analysis. Although this analysis accurately identifies BZP in a sample it is not a useful tool for the field officer and slows down sample processing in the laboratory. We have an ongoing collaboration with the Orange County Sheriff’s Department in California to develop a distinct test for BZP.   

A major focus of our work is to produce new non-destructive presumptive tests that can eliminate false positives. For example, a series consisting of Wagner, Marquis and cobalt thiocyanate reagents is used by the NYCPD for the identification of cocaine and opioids. 1 Unfortunately, this sequence of tests results in false positives for cocaine with the following compounds: atropine, methadone, nicotine, phencyclidine and scopolamine.  Additionally, the evolution of color observed on application of Marquis reagent is due to the transient formation of free radicals. Ultimately this test is destructive and it is impossible to recover the analyte after its application. 

New tests developed should be:

• Robust
• Inexpensive
• Easy
• Specific
• Non-destructive

We are investigating d10 metal halide cluster compounds as fluorescent indicators. The compounds are known to produce fluorescent complexes with amines. Current work has focused on developing fluorescent tests based on CuI. We have been able to produce test strips that positively identify BZP, Cocaine HCl, PCP, TFMPP, and nicotine.  Each of these substances gives a unique color. These tests are sensitive and can give a visually detectable response with as little as 5 ug of analyte. We are now using chemical modification to increase the range of substances that give a response. Ultimately we will couple new light sources, fluorescent indicators, and digitizing systems to produce small handheld systems that will allow assessment of multiple indicators in the field.

1) Swiatko, J.D.F., PR, Zedeck, MS, Further studies on spot tests and microcrystal tests for identification of cocaine Journal of Forensic Sciences, 2003. 48(3): p. 1-5.