PMID- 28875194
OWN - NLM
STAT- PubMed-not-MEDLINE
DCOM- 20180723
LR  - 20180723
IS  - 1364-5528 (Electronic)
IS  - 0003-2654 (Linking)
VI  - 142
IP  - 19
DP  - 2017 Sep 25
TI  - Correcting transmission losses in short-wave infrared spatially offset Raman 
      spectroscopy measurements to enable reduced fluorescence through-barrier 
      detection.
PG  - 3725-3732
LID - 10.1039/c7an00187h [doi]
AB  - Spatially offset Raman spectroscopy (SORS) is a proven technique for sub-surface 
      detection. SORS is able to separate Raman signals from a container and its 
      contents, thereby demonstrating application to through-barrier detection for 
      defence and security. Whilst SORS has been demonstrated to reduce fluorescence 
      from the barrier (or surface), fluorescence from the sample (or sub-surface) can 
      still be problematic for some materials when using Raman excitation wavelengths 
      typical in commercially available instrumentation (e.g. 785 nm). Previous work 
      has demonstrated that short-wave infrared (SWIR) excited SORS (e.g. 1064 nm) can 
      reduce fluorescence from the sample and barrier, thereby providing the potential 
      to detect a wider range of materials through a wider range of barriers. In this 
      paper we highlight an additional challenge for detection through some plastic 
      container materials (e.g. high density polyethylene (HDPE) and other opaque 
      plastics) that absorb and scatter both incident and Raman scattered photons in 
      the SWIR band, leading to distortion of the resultant SORS spectrum. The 
      existence of this effect and its impact is explored, along with a potential 
      solution to overcome this challenge that uses multi-wavelength Raman excitation 
      to avoid the detrimental HDPE absorption region.
FAU - Hopkins, R J
AU  - Hopkins RJ
AD  - Defence Science and Technology Laboratory, Porton Down, Salisbury, SP4 0JQ, UK. 
      rjhopkins@dstl.gov.uk.
FAU - Lee, L
AU  - Lee L
FAU - Shand, N C
AU  - Shand NC
LA  - eng
PT  - Journal Article
PL  - England
TA  - Analyst
JT  - The Analyst
JID - 0372652
EDAT- 2017/09/07 06:00
MHDA- 2017/09/07 06:01
CRDT- 2017/09/07 06:00
PHST- 2017/09/07 06:00 [pubmed]
PHST- 2017/09/07 06:01 [medline]
PHST- 2017/09/07 06:00 [entrez]
AID - 10.1039/c7an00187h [doi]
PST - ppublish
SO  - Analyst. 2017 Sep 25;142(19):3725-3732. doi: 10.1039/c7an00187h.