In:
Chinese Journal of Chemistry, Wiley, Vol. 28, No. 11 ( 2010-11), p. 2233-2239
Abstract:
Under the conditions of reacting at 100°C for 8 min and irradiating with the infrared light for 15 min, methylene blue (MEB) could emit weak room temperature phosphorescence (RTP) on the cellulose acetate membrane (CAM) using Pb 2+ as the ion perturber in the NH 3 ‐NH 4 Cl (pH=9.80) solution. MEB was oxidized by H 2 O 2 , which caused the RTP of the system to enhance. Cu 2+ could catalyze the reaction of H 2 O 2 oxidizing MEB, which caused the RTP of the system to enhance sharply. The Δ I p ( I p0 − I p , the I p0 and I p were RTP intensity of the blank reagent and RTP intensity of the test reagent, respectively) of the catalytic system was 133.6, which was 4.1 times larger than that without infrared light irradiation (33.1). Its Δ I p was proportional to the content of Cu 2+ . Thus, a new catalytic solid substrate room temperature phosphorimetry (SSRTP) for the determination of trace copper has been established. The limit of quantization (LOQ) of this method was 0.12 ag·spot −1 (sample volume: 0.40 µL·spot −1 , corresponding concentration: 3.0×10 −16 g·mL −1 ), showing high sensitivity. This method not only has been successfully applied to the determination of trace copper in the tobacco, tea and human serum, but also could predict human diseases. The catalytic reaction was first order reaction, whose activation energy ( E ) was 18.17 kJ·mol −1 and rate constant ( k ) was 3.4×10 −4 s −1 . At the same time, the mechanism of catalytic SSRTP for the determination of trace copper was discussed.
Type of Medium:
Online Resource
ISSN:
1001-604X
,
1614-7065
DOI:
10.1002/cjoc.201090369
Language:
English
Publisher:
Wiley
Publication Date:
2010
detail.hit.zdb_id:
2144352-X
SSG:
6,25
