title: Novel and sensitive methods for the determination of dopamine based on the resonance Rayleigh scattering, second-order scattering and frequency doubling scattering quenching effects.
abstract: Three novel methods were designed for the determination of dopamine (DA) by means of the quenching effects on resonance Rayleigh scattering (RRS) and non-linear scattering such as second-order scattering (SOS) and frequency doubling scattering (FDS) intensities. In Britton-Robinson buffer medium (pH 6.02), I(3)(-) could react with DA to produce I(-), which resulted in the decreases of the RRS, SOS and FDS intensities of the ethyl violet (EV)-I(3)(-) system, and the decreases of scattering intensity (DeltaI) were directly proportional to the concentrations of DA in a certain range. The detection limit (3sigma) for DA was 0.0195 micromol/L for the RRS method, 0.286 micromol/L for the SOS method and 0.0985 micromol/L for the FDS method, respectively. In this work, the characteristics of absorption, RRS, SOS and FDS spectra of this reaction have been studied; the optimum reaction condition and influencing factors have been investigated. The methods were applied to the determination of DA in pharmaceutical samples with satisfactory results.
authors.affiliation: School of Chemistry and Chemical Engineering, Education Ministry Key Laboratory on Luminescence and Real-Time Analysis, Southwest University, Chongqing 400715, China.
authors.forename: Yan
authors.initials: Y
authors.lastname: Ma
authors.forename: Nian Bing
authors.initials: NB
authors.lastname: Li
authors.forename: Hong Qun
authors.initials: HQ
authors.lastname: Luo
mesh_terms: D004298:Dopamine / Q000032:analysis*; D017613:Iodine Compounds / Q000737:chemistry; D008027:Light; D012394:Rosaniline Dyes / Q000737:chemistry; D012542:Scattering, Radiation; D012680:Sensitivity and Specificity; D013050:Spectrometry, Fluorescence / Q000379:methods*; D013053:Spectrophotometry / Q000379:methods*
chemical_list: D017613:Iodine Compounds; D012394:Rosaniline Dyes; C034887:ethyl violet; D004298:Dopamine