title: Chemiluminescence of synephrine based on the cerium(IV)-rhodamine B system.
abstract: A new chemiluminescence (CL) method is described for the determination of synephrine. It is based on the reaction between synephrine and Ce(IV) in a nitric acid medium and measurement of the CL intensity produced by rhodamine B used as a luminophore, similar to luminol or lucigenin in basic media, instead of as a sensitizer. In the optimum conditions, the increase of CL intensity was correlated with synephrine concentration over the range 5.0 x 10(-9)-1.0 x 10(-6) g/mL with a detection limit of 1.0 x 10(-9) g/mL. The relative standard deviation (RSD) was 2.9% for 1.0 x 10(-7) g/mL synephrine (n = 11). The method was applied to the determination of a drug in herbal products, citrus fruit and biological samples, with satisfactory results. The results given by the proposed method are in good agreement with those given by HPLC-UV and UV spectrophotometry.
authors.affiliation: College of Chemistry and Chemical Engineering, Institute of Analytical Sciences, Key Laboratory of Eco-environments in Three Gorges Reservoir Region (Ministry of Education), Southwest University, Beibei, Chongqing 400715, People's Republic of China.
authors.forename: Ruifen
authors.initials: R
authors.lastname: Wang
authors.forename: Lijuan
authors.initials: L
authors.lastname: Wan
authors.forename: Qian
authors.initials: Q
authors.lastname: Li
authors.forename: Xidong
authors.initials: X
authors.lastname: Liu
authors.forename: Yuming
authors.initials: Y
authors.lastname: Huang
mesh_terms: D002563:Cerium / Q000737:chemistry*; D002957:Citrus / Q000737:chemistry; D017022:Flow Injection Analysis; D005456:Fluorescent Dyes / Q000737:chemistry; D005638:Fruit / Q000737:chemistry; D006801:Humans; D049449:Luminescence; D015394:Molecular Structure; D012235:Rhodamines / Q000737:chemistry*; D013578:Synephrine / Q000032:analysis* / Q000737:chemistry / Q000652:urine*
chemical_list: D005456:Fluorescent Dyes; D012235:Rhodamines; D002563:Cerium; C029773:rhodamine B; D013578:Synephrine