In this master's project the detection of the herbicides atrazine and prometryn will be investigated using the surface-enhanced Raman scattering (SERS) technique. In this case, the herbicides will be dissolved at different concentrations in silver colloids (AgNPs: silver nanoparticles), being the development of sensors the broader goal of this project. The herbicides atrazine and prometryn belong to the class of s-triazines owing properties classified as toxic agents that may cause harm to humans. Alternatively, the detection of atrazine and prometryn will also be performed by impedance spectroscopy. In this case the sensing units, composed by Layer-by-Layer (LbL) films of lipid/AgNPs deposited onto interdigitated electrodes, are immersed in aqueous solutions containing different concentrations of prometryn or atrazine. SERS measurements will be also carried out directly from the sensing units after impedance measurements, thus allowing complementary analysis. The limits for drinking water associated with these pesticides are about 10-10 mol/L. Therefore, detection of such concentration is a challenge that requires the use of techniques of high sensitivity and selectivity, which is the case of SERS, besides impedance spectroscopy.
News published in Agência FAPESP Newsletter about the scholarship: