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									Portable
Raman
Spectroscopy
as a Functional
Tool in
Homeland
Security
Izake, E. , Forensic and homeland
security applications of modern
portable Raman spectroscopy.
Forensic Science International.
(2010), vol 9, pp. 1 – 8

Kassandra Luening and Neil Rybak
Conventional Techniques

   GC/MS
   HPLC/MS
   THZ (Terahertz radiation spectroscopy)

   Limitations
       Operator must come into contact with potentially
        hazardous samples
       Instruments must be disposed of or decontaminated after
        contact with hazardous materials
       These techniques are not portable. Require the movement
        of complex instruments
Portable Raman Instruments
   Allows for the portability
    of Raman spectroscopy
   High volumes of samples
    can be scanned, without
    the operator coming into
    contact with the sample,
    and the units are now
    fully portable
Chemistry of Raman Spectroscopy
 Monochromatic       light applied to sample
 Incident light is scattered
     Rayleigh (elastic) and Raman (inelastic)
 Rayleigh   scatter is filtered out
 The returned scattered light is a different
  wavelength
 This difference corresponds to an energy
  shift which provides a unique chemical
  fingerprint
Advantages of Raman Spectroscopy
   Provides molecular fingerprints of each analyte,
    providing the possibility of highly selective
    determinations
   Applicable to any optically accessible sample; organic,
    inorganic, or biological
   Solid, liquid, gaseous, transparent and non-transparent
    samples can be measured
   Aqueous solutions present no special technical
    problems
   Sample scanning is non-invasive
   Detection can be of sample sizes from 1 µm – dm2 and
    distances from millimetres up to several metres
   Raman fingerprint is independent of excitation
    wavelength, allowing for the use of any laser for
    excitation
   Detection can be done day and night without the
    presence of background signals due to ambient light
    interference
   Raman spectroscopy has become fully portable
Examples of Portable Raman in Use
 Has  been used to identify illicit drugs using
  NIR laser excitation2
 Capable of rapid detection, acquisition
  times of 1 minutes when analyzing
  amphetamine street samples3
 Ultra trace amounts of illicit drugs (5 – 20
  µm in size) found under nail varnish in a
  non-destructive manner in under three
  minutes4
Stand-off Raman detection of hazardous
substances
   Constructing a gated
    detector system can
    restrict the laser pulse of
    the light source
   Data collected at the
    time the laser is
    expected to arrival at
    the sample
   Allows for sample
    detection from
    distances up to 100
    metres5
Ahura First Defender


   Currently in use by
    emergency response
    teams6
   Has been used to assist the
    FBI to identify hazardous
    materials7
   Results of the analysis of
    the “First Defender”
    instrument have been used
    in court to assist in a
    conviction9
Ahura TruNarc




 The ease of use of the instrument and the
 library of samples “potentially eliminates
 the need for a chemist to testify”
    Simple non-expert use of the instrument
Rigaku Firstguard Handeld Analyzer8

   No sample prep
    needed
   Operated like a point
    and shoot camera
   Delivers results in
    seconds with no
    chance of human error
   User can either build
    their own database or
    use supplied library
Conclusions
   Portable Raman has been shown to be more
    effective than conventional methods in the
    detection of drugs and other hazardous
    samples
       No contact of sample with analyst or instrument
       High throughput capability
       Can be used in close proximity of sample or at
        distances
       Can analyze organic, inorganic and biological
        samples through containers, in both light and
        dark environments
       New portable instrumentation is user friendly
        allowing non expert users to easily identify
        samples
References
1.   Izake, E. , Forensic and homeland security applications of modern portable
     Raman spectroscopy. Forensic Science International. (2010), vol 9, pp. 1 – 8
2.   S.E.J. Bell, D.T. Burns, A.C. Dennnis, L.J. Matchett, J.S. Speers, Composition and
     profiling of seized ecstasy tablets by Raman spectroscopy, Analyst 125 (10) (2000)
     541 – 544
3.   E. Katainen, M. Elomaa, M. Laakkonen, E. Sippola, P. Niemela, K. Janne Suhonen,
     Jarvinen, Quantification of the amphetamine content in seized street samples by
     Raman Spectroscopy, J. Forensic Sci. 52 (1) (2007) 88 – 90
4.   E. Ali, H. Edwards, M. Hargreaves, I. Scowen, Raman spectroscopic investigation
     of cocaine hydrochloride on human nail in a forensic context, Anal. Bioanal.
     Chem. 390 (4) (2008) 1159 – 1166
5.   S.K. Sharma, New trends in telescopic remote Raman spectroscopic
     instrumentation, Spectrochim. Acta Part A 68 (5) (2007) 1008 – 1022
6.   City of Albany, NY. Department of Fire, Emergency Services and Code
     Enforcement Accomplishments for 2009.
7.   Monmouth County Health Department Hazardous Materials Response/UST Units
     2009 Annual Report
8.   Information obtained from brochure provided by contact with Rigaku Raman
     Technologies (www.rigakuraman.com)
9.   Rains, S. (2011, May 7), Convict Guilty of Courthouse Hoax. Lawton Constitution
     (http://www.swoknews.com/main.asp?SectionID=11&SubSectionID=98&ArticleID=
     34618)
Ahura TruScan in use

								
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