title: Multiobjective evolutionary optimisation for surface-enhanced Raman scattering.
abstract: In most optimisation experiments, a single parameter is first optimised before a second and then third one are subsequently modified to give the best result. By contrast, we believe that simultaneous multiobjective optimisation is more powerful; therefore, an optimisation of the experimental conditions for the colloidal SERS detection of L-cysteine was carried out. Six aggregating agents and three different colloids (citrate, borohydride and hydroxylamine reduced silver) were tested over a wide range of concentrations for the enhancement and the reproducibility of the spectra produced. The optimisation was carried out using two methods, a full factorial design (FF, a standard method from the experimental design literature) and, for the first time, a multiobjective evolutionary algorithm (MOEA), a method more usually applied to optimisation problems in computer science. Simulation results suggest that the evolutionary approach significantly out-performs random sampling. Real experiments applying the evolutionary method to the SERS optimisation problem led to a 32% improvement in enhancement and reproducibility compared with the FF method, using far fewer evaluations.
authors.affiliation: School of Chemistry, University of Manchester, Manchester Interdisciplinary Biocentre, 131 Princess Street, Manchester, M1 7DN, UK. roger.jarvis@manchester.ac.uk
authors.forename: Roger M
authors.initials: RM
authors.lastname: Jarvis
authors.forename: William
authors.initials: W
authors.lastname: Rowe
authors.forename: Nicola R
authors.initials: NR
authors.lastname: Yaffe
authors.forename: Richard
authors.initials: R
authors.lastname: O'Connor
authors.forename: Joshua D
authors.initials: JD
authors.lastname: Knowles
authors.forename: Ewan W
authors.initials: EW
authors.lastname: Blanch
authors.forename: Royston
authors.initials: R
authors.lastname: Goodacre
mesh_terms: D003102:Colloids / Q000032:analysis; D003545:Cysteine / Q000032:analysis*; D013059:Spectrum Analysis, Raman / Q000295:instrumentation / Q000379:methods*
chemical_list: D003102:Colloids; D003545:Cysteine