Noble Metal Nanoparticles

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Noble Metal Nanoparticles
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Noble Metal Nanoparticles
D 24.8 4.1 nm
50 nm
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Partition Layers to Detect Non-Traditional
Analytes with SERS Kyle Bantz
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Polychlorinated Biphenyls (PCBs)

• Present in soil, water, and air worldwide
• Classified as persistent organic pollutants
• Analysis traditionally done by GC-MS
• Complicated by low
• concentrations and
• multiple congeners
• Prohibitively difficult
• for in situ environmental
• analysis

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Partitioning PCBs
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Other Experiments

• Use band intensities and shifts to understand the
  partitioning mechanism
• Environmental interferants not a problem
• Substrates can be reused

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Are you getting the concept?
Kyle fabricates a new Ag SERS substrate and wants
to calculate the EF. She doses the substrate
with benzenethiol (packing density 6.8 x 1014
molecules/cm2), and measures the spectrum with a
laser spot size of 1.26 mm2. The intensity of the
1000 cm-1 shift ring breathing stretch is 35793
adus. For her standard, she puts undiluted
benzenethiol (r 1.073 g/cm3) into a cuvette
with a known probe volume of 0.00413 mL and
measures a 1000 cm-1 shift band intensity of
36364 adus. What is the EF (assuming that the
laser power and collection time were the same for
both measurements)?