title: Determination of dopamine at the nanogram level based on the formation of Prussian blue nanoparticles by resonance Rayleigh scattering technique.
abstract: In pH 2.6 HCl solution, dopamine (DA) could reduce Fe(III) to Fe(II), which further reacted with [Fe(CN)(6)](3-) to form a Fe(3)[Fe(CN)(6)](2) complex. By virtue of hydrophobic force and Van der Waals force, the complex aggregated to form Fe(3)[Fe(CN)(6)](2) nanoparticles with the average diameter of about 20 nm. This resulted in a significant enhancement of resonance Rayleigh scattering (RRS). The maximum wavelength of the ion-association complex was located at about 350 nm. The increment of scattering intensity (ΔI(RRS)) was directly proportional to the concentration of DA in the range of 0.06-1.0 μg/mL. This method has high sensitivity and the detection limit (3σ) for DA was 3.43 ng/mL. In this work, the characteristics of absorption and RRS spectra of this reaction have been studied. The optimum reaction condition and influencing factors have been investigated. The method was applied to the determination of DA in pharmaceutical samples with satisfactory results. Furthermore, the reaction mechanism and the reasons of RRS enhancement have been explored.
authors.affiliation: Key Laboratory on Luminescence and Real-Time Analysis, Ministry of Education, School of Chemistry and Chemical Engineering, Southwest University, Chongqing 400715, PR China.
authors.forename: Jiang Xue
authors.initials: JX
authors.lastname: Dong
authors.forename: Wei
authors.initials: W
authors.lastname: Wen
authors.forename: Nian Bing
authors.initials: NB
authors.lastname: Li
authors.forename: Hong Qun
authors.initials: HQ
authors.lastname: Luo
mesh_terms: D000042:Absorption; D000143:Acids / Q000737:chemistry; D002138:Calibration; D004298:Dopamine / Q000032:analysis*; D005295:Ferrocyanides / Q000737:chemistry*; D057927:Hydrophobic and Hydrophilic Interactions; D007202:Indicators and Reagents; D007501:Iron / Q000737:chemistry; D008027:Light; D053758:Nanoparticles / Q000737:chemistry* / Q000648:ultrastructure; D036103:Nanotechnology / Q000379:methods*; D010316:Particle Size; D012542:Scattering, Radiation; D012997:Solvents / Q000737:chemistry; D013057:Spectrum Analysis; D014867:Water / Q000737:chemistry
chemical_list: D000143:Acids; D005295:Ferrocyanides; D007202:Indicators and Reagents; D012997:Solvents; D014867:Water; D007501:Iron; C000170:ferric ferrocyanide; D004298:Dopamine