Abstract:
The present work reports on the possibility of polycyclic aromatic hydrocarbons (PAHs) detection by surface
enhanced Raman scattering (SERS) on substrates coated with colloidal silver stabilized with
cetyltrimethylammonium bromide (CTAB). It was shown that cetyltrimethylammonium bromide acts not only
as a stabilizer of metal nanoparticles, but also as modifying agent that promotes the concentration of hydrophobic
PAH molecules near the amplified electromagnetic field of plasmon silver nanoparticles.
Anthracene and pyrene were used as model analytes. To determine the sensitivity of the prepared SERS active
coating, ethanol solutions of the analyzed substances with concentrations in the range of 2·10-4 — 10-6
mol/L were used. The lowest concentrations of solutions for which anthracene and pyrene are found on the
tested substrates were equal to 2.5·10-6 M and 5·10-5 M, respectively. These results indicate that substrates are
more sensitive to anthracene than to pyrene. The work also shows that various PAH molecules can be detected
by characteristic peaks in a complex mixture without preliminary separation of the components.
