Determination of trace silver by solid substrate room temperature phosphorescence quenching method based on lead carboxymethyl cellulose particles (Pb(CMC)2) containing luminescent salicyl fluorenes molecules.
Luminescent particles of lead carboxymethyl cellulose (Pb(CMC)2) containing salicyl fluorones (THBF), Pb(CMC)2-THBF were synthesized by the sol-gel method, using sodium carboxymethyl cellulose (NaCMC) as precursor and Pb2+ as precipitant. Pb(CMC)2-THBF can emit the intense and stable solid substrate room temperature phosphorescence (SS-RTP) on filter paper. And EDTA can chelate Pb2+ in Pb(CMC)2-THBF, causing it to decompose into aqueous soluble components PbY2-, CMC- and THBF, which can react with Ag+ to form Ag(CMC)2-THBF, causing the decrease of phosphorescence intensity. Based on the facts above, a new method for the determination of trace silver by SS-RTP quenching method was established. The linear range of this method is 8.0-40.0 fg spot(-1) (20.0-100.0 pg ml(-1)), with a detection limit (LD) of 2.2 fg spot(-1) (corresponding to a concentration range of 5.5 x 10(-13) g ml(-1)), and the regression equation of working curve is DeltaI(p) = 12.56 + 0.5527C(Ag+) (fg spot(-1), 0.4 microl spot(-1)), n = 8, r = 0.9992. This method has been applied to the determination of trace silver in human hair and tea sample with satisfactory results. The mechanism of SS-RTP emission is also discussed.
Jiaming
Liu
L
Department of Chemistry, Zhangzhou Normal College, Zhangzhou 363000, PR China. zzsliujiaming@163.com
Wenqi
Li
L
Xuelin
Li
L
Hailing
Chen
C
Qiaomei
Lu
L
Longdi
Li
L
Zhimin
Li
L
Guohui
Zhu
Z
Cuilian
Chen
C
D002266:Carboxymethylcellulose Sodium / Q000031:analogs & derivatives* / Q000737:chemistry*; D005449:Fluorenes / Q000737:chemistry*; D008163:Luminescent Measurements / Q000379:methods*; D009942:Organometallic Compounds / Q000737:chemistry*; D012834:Silver / Q000032:analysis* / Q000737:chemistry*; D013057:Spectrum Analysis; D013696:Temperature; D013997:Time Factors
D005449:Fluorenes; D009942:Organometallic Compounds; C506568:lead carboxymethyl cellulose; D012834:Silver; D002266:Carboxymethylcellulose Sodium