title: Determination of trace formaldehyde by solid substrate-room temperature phosphorescence quenching method based on the rose bengal-potassium bromate-Tween-80 system.
abstract: A new method for the determination of trace formaldehyde by solid substrate-room temperature phosphorescence quenching method has been proposed. It is based on the facts that rose bengal (R) can emit intense and stable room temperature phosphorescence on the solid substrate of filter paper (SS-RTP). Potassium bromate (KBrO(3)) can oxidize R, which causes the quenching of RTP. In the presence of HCHO, it can react with KBrO(3) to form Br(2) and Br(2) can oxidize R, which causes smart quenching of RTP. The phosphorescence intensity (DeltaI(p)) is directly proportional to the concentration of HCHO. In the presence of Tween-80, the DeltaI(p) will be increased to 9.1 times higher than that without it. The linear range of this method is 0.016-1.6fgspot(-1) (corresponding concentration: 0.040-4.0 pgml(-1), 0.40 microlspot(-1)) with the detection limit of 4.5agspot(-1) (corresponding concentration: 1.1 x 10(-14) gml(-1)). The regression equation for working curve is DeltaI(p)=136.6+28.28m(HCHO)fgspot(-1) (r=0.9935, n=6). This method is sensitive, simple, rapid and has been applied to the determination of trace formaldehyde in real samples with satisfactory results. The mechanism of determination of trace formaldehyde by SS-RTP quenching method based on the rose bengal-KBrO(3)-Tween-80 system is also discussed.
authors.affiliation: Department of Chemistry and Environmental Science, Zhangzhou Normal College, Zhangzhou 363000, PR China.
authors.forename: Jiaming
authors.initials: J
authors.lastname: Liu
authors.forename: Tianlong
authors.initials: T
authors.lastname: Yang
authors.forename: Guohui
authors.initials: G
authors.lastname: Zhu
authors.forename: Hailing
authors.initials: H
authors.lastname: Chen
authors.forename: Pingping
authors.initials: P
authors.lastname: Li
authors.forename: Xuan
authors.initials: X
authors.lastname: Lin
authors.forename: Xiaomei
authors.initials: X
authors.lastname: Huang
mesh_terms: D001959:Bromates / Q000737:chemistry*; D002021:Buffers; D003890:Desiccation; D005557:Formaldehyde / Q000032:analysis*; D007202:Indicators and Reagents; D008163:Luminescent Measurements / Q000379:methods*; D016877:Oxidants / Q000737:chemistry; D011136:Polysorbates / Q000737:chemistry*; D012015:Reference Standards; D012395:Rose Bengal / Q000737:chemistry*; D013696:Temperature; D013997:Time Factors; D014867:Water / Q000737:chemistry
chemical_list: D001959:Bromates; D002021:Buffers; D007202:Indicators and Reagents; D016877:Oxidants; D011136:Polysorbates; C019536:potassium bromate; D014867:Water; D005557:Formaldehyde; D012395:Rose Bengal