Determination of Trace Copper by Solid Substrate–Room Temperature Phosphorescence Quenching Method Based on Lead Carboxymethyl Cellulose [Pb(CMC)₂] Particles Containing Luminescent Salicyl Fluorones Molecules

Abstract

Luminescent particles of lead carboxymethyl cellulose [Pb(CMC)₂] that contain luminescent salicyl fluorones (SAF) {[Pb(CMC)₂]‐SAF} were synthesized by sol‐gel method, using sodium carboxymethyl cellulose (NaCMC) as precursor and Pb²⁺ as precipitator. [Pb(CMC)₂]‐SAF can emit intense and stable solid substrate–room temperature phosphorescence (SS‐RTP) on filter paper. EDTA (ethylenediaminetetraacetic acid) can chelate the Pb²⁺ in [Pb(CMC)₂]‐SAF, causing it to decompose into aqueous soluble components PbY^2–, CMC^–, and SAF, and these components can react with Cu²⁺ to form [Cu(CMC)₂]‐SAF, causing decrease of phosphorescence intensity. Based on the facts above, a new method for the determination of trace mercury by SS‐RTP quenching method was established. This method has been applied to the determination of trace copper in human hair and tea samples with satisfactory results.

Keywords:

• Determination of copper
• quenching method
• solid substrate–room temperature phosphorescence

Acknowledgment

This work was supported by Fu jian Province Natural Science Foundation (grant no. C 0510028, D 0510027).