title: Highly sensitive detection of chromium (III) ions by resonance Rayleigh scattering enhanced by gold nanoparticles.
abstract: Simple and sensitive determination of chromium (III) ions (Cr(3+)) has potential applications for detecting trace contamination in environment. Here, the assay is based on the enhancement of resonance Rayleigh scattering (RRS) by Cr(3+)-induced aggregation of citrate-capped gold nanoparticles (AuNPs). Transmission electron microscopy (TEM) and UV-vis absorption spectroscopy were employed to characterize the nanostructures and spectroscopic properties of the Cr(3+)-AuNP system. The experiment conditions, such as reaction time, pH value, salt concentration and interfering ions, were investigated. The combination of signal amplification of Cr(3+)-citrate chelation with high sensitivity of RRS technique allow a selective assay of Cr(3+) ions with a detection limit of up to 1.0 pM. The overall assay can be carried out at room temperature within only twenty minutes, making it suitable for high-throughput routine applications in environment and food samples.
authors.affiliation: Department of Pulmonary Medicine, The First Affiliated Hospital of Jinan University, Guangzhou 510630, China; Institute of Respiratory Diseases, Guangdong Medical College, Zhanjiang 524001, China.
authors.forename: Min
authors.initials: M
authors.lastname: Chen
authors.forename: Huai-Hong
authors.initials: HH
authors.lastname: Cai
authors.forename: Fen
authors.initials: F
authors.lastname: Yang
authors.forename: Dewen
authors.initials: D
authors.lastname: Lin
authors.forename: Pei-Hui
authors.initials: PH
authors.lastname: Yang
authors.forename: Jiye
authors.initials: J
authors.lastname: Cai
mesh_terms: D002412:Cations / Q000032:analysis; D002857:Chromium / Q000032:analysis*; D019343:Citric Acid / Q000737:chemistry; D006046:Gold / Q000737:chemistry*; D007477:Ions / Q000032:analysis; D008027:Light; D057230:Limit of Detection; D053768:Metal Nanoparticles / Q000737:chemistry* / Q000648:ultrastructure; D012542:Scattering, Radiation; D013053:Spectrophotometry
chemical_list: D002412:Cations; D007477:Ions; D002857:Chromium; D019343:Citric Acid; D006046:Gold
keywords: Cr(3+) ion; Gold nanoparticles; Nanoparticle aggregates; Resonance Rayleigh scattering; Sensors