title: Determination of trace lead by solid substrate room temperature phosphorescence enhancing method based on heavy atom effect and dissoluble manganese supramolecule containing rhodamine 6G luminescent particles.
abstract: Dissoluble manganese supramolecule containing rhodamine 6G luminescent particles (M2) are synthesized, based on dissoluble manganese supramolecule (M1) doping rhodamine 6G (R.6G), by crystalline method. The particle diameters of M1 and M2 determined by ETM are both of micron degree. M1 and M2 can emit solid substrate room temperature phosphorescence (SS-RTP) on filter paper. The transition probability from the singlet state (S1) to triplet state (T1) of the luminescent molecules was greatly enhanced, based on the increment of luminescent molecules for each spot and the heavy atom effect of certain amount of Pb2+. As a result, the phosphorescence intensity (Ip) of M2 was increased sharply, and the enhancing value of phosphorescence intensity (DeltaIp) is directly proportional to the concentration of Pb2+. Thus, a new method of SS-RTP enhancing for the determination of trace lead is established based on manganese supramolecule containing rhodamine 6G luminescent particles. The linear range of this method is 0.0040-0.400 pg spot-1 of Pb2+ (corresponding concentration, 0.01-1.0 ng mL-1; sample volume, 0.4 microL spot-1), with a detection limit (LD) of 0.0011 pg spot-1 (corresponding concentration, 2.8x10(-12) g mL-1 of Pb2+, n=11). For the working solutions containing 0.0040 and 0.40 ng mL-1 of Pb2+, they were determined repeatedly for seven times, respectively. The R.S.D.s were 3.2 and 3.8%, respectively. This method has good repeatability, sensitivity and high precision. It has been applied to the determination of trace lead in human hair and tea samples with satisfactory results.
authors.affiliation: Department of Chemistry and Environment Science, Zhangzhou Normal College, Zhangzhou 363000, PR China.
authors.forename: Xuan
authors.initials: X
authors.lastname: Lin
authors.forename: Ruo-Hong
authors.initials: RH
authors.lastname: Wu
authors.forename: Xiao-Ju
authors.initials: XJ
authors.lastname: Li
authors.forename: Li
authors.initials: L
authors.lastname: Chen
authors.forename: Qing-Wei
authors.initials: QW
authors.lastname: Lin
authors.forename: Wen-Yan
authors.initials: WY
authors.lastname: Gao
authors.forename: Ai-Fang
authors.initials: AF
authors.lastname: Zheng
authors.forename: Jia-Ming
authors.initials: JM
authors.lastname: Liu
authors.forename: Guo-Hui
authors.initials: GH
authors.lastname: Zhu
authors.forename: Xiao-Mei
authors.initials: XM
authors.lastname: Huang
mesh_terms: D002413:Cations, Divalent / Q000032:analysis; D005504:Food Analysis / Q000379:methods; D006197:Hair / Q000737:chemistry; D006801:Humans; D007854:Lead / Q000032:analysis*; D008345:Manganese / Q000737:chemistry*; D010316:Particle Size; D012235:Rhodamines / Q000737:chemistry*; D012680:Sensitivity and Specificity; D012995:Solubility; D013050:Spectrometry, Fluorescence; D013662:Tea / Q000737:chemistry
chemical_list: D002413:Cations, Divalent; D012235:Rhodamines; D013662:Tea; C026188:rhodamine 6G; D007854:Lead; D008345:Manganese