title: Evaluation of Colloids and Activation Agents for Determination of Melamine Using UV-SERS.
abstract: UV-SERS measurements offer a great potential for environmental or food (detection of food contaminats) analytics. Here, the UV-SERS enhancement potential of various kinds of metal colloids, such as Pd, Pt, Au, Ag, Au-Ag core-shell, and Ag-Au core-shell with different shapes and sizes, were studied using melamine as a test molecule. The influence of different activation (KF, KCl, KBr, K(2)SO(4)) agents onto the SERS activity of the nanomaterials was investigated, showing that the combination of a particular nanoparticle with a special activation agent is extremely crucial for the observed SERS enhancement. In particular, the size dependence of spherical nanoparticles of one particular metal on the activator has been exploited. By doing so, it could be shown that the SERS enhancement increases or decreases for increasing or decreasing size of a nanoparticle, respectively. Overall, the presented results demonstrate the necessity to adjust the nanoparticle size and the activation agent for different experiments in order to achieve the best possible UV-SERS results.
authors.forename: Evelyn
authors.initials: E
authors.lastname: Kämmer
authors.forename: Thomas
authors.initials: T
authors.lastname: Dörfer
authors.forename: Andrea
authors.initials: A
authors.lastname: Csáki
authors.forename: Wilm
authors.initials: W
authors.lastname: Schumacher
authors.forename: Paulo Augusto
authors.initials: PA
authors.lastname: Da Costa Filho
authors.forename: Nicolae
authors.initials: N
authors.lastname: Tarcea
authors.forename: Wolfgang
authors.initials: W
authors.lastname: Fritzsche
authors.forename: Petra
authors.initials: P
authors.lastname: Rösch
authors.forename: Michael
authors.initials: M
authors.lastname: Schmitt
authors.forename: Jürgen
authors.initials: J
authors.lastname: Popp