Determination of trace calcium by solid substrate-room temperature phosphorimetry

Abstract

A new method for the determination of trace calcium by solid substrate-room temperature phosphorimetry is established. It is based on the fact that chromeazurols azurol S-phenanthroline-NaCMC (CAS-phen-NaCMC) system can emit strong and stable room temperature phosphorescence (RTP) on the solid substrate in the filter paper. Ca 2+ and phenanthroline can form complex ion Ca(phen) 3 2+, which will form complex [Ca(phen) 3(CAS) 2] with CAS. In the result, the number of CAS molecules in each spot increased, causing sharp increase of the RTP signal of the CAS-phen-NaCMC system.