On-Line Chemiluminescence Detection for Capillary Ion Analysis

Abstract

Highly sensitive chemiluminescence detection for capillary ion analysis has been developed. The new idea lies in using the chemiluminescence reagent luminol as a component of the separation electrolyte, thus preventing loss of the light signal where luminol and H 2 O 2 are mixed in advance in conventional flow injection analysis or ion chromatography chemiluminescence detection. Signal enhancement is achieved by sample stacking injection in the electrophoresis process. The detection limit (S/N ) 3) of 20 zmol (5 × 10 -13 mol/L) for cobalt(II) is ∼2 orders of magnitude better than the most sensitive results (1.7 × 10 -11 mol/L) reported so far. Detection limits are 2 amol, 80 amol, 740 amol, and 100 fmol for copper(II), nickel(II), iron(III), and manganese(II), respectively. The sensitivity is significantly better than that in the electrochemical detection and the commonly used UV detection in capillary ion analysis. The capillary electrophoresischemiluminescence detector has been used to separate five metal ions, cobalt(II), copper(II), nickel(II), iron(III), and manganese(II), within 8 min with an average theoretical plate number of 4.6 × 10 5 .

Integration of a flow-type chemiluminescence detector on a glass electrophoresis chip

“…In conventional flow injection CL analysis (FIA) [34] and liquid chromatography CL analysis [35,36], TCPO stream and hydrogen peroxide stream mix in advance and then react with analytes. However, when sample injection is very small (i.e., nanoliters), such a mixing mode might lead to a significant decrease in sensitivity [19]. To be conveniently operated and improve the sensitivity, the mixed solution of TCPO and H 2 O 2 , used as the CL reagent, was introduced.…”

“…Besides, there are more advantages in CL detection, such as wide dynamic range, simple instrumentation and versatility of use. Many CL systems have been well characterized and coupled to CE including peroxyoxalate [18], luminol [19], and barium peroxide [20]. Since these characters of CL match the demands of miniaturization and integration, CL will be a promising detection method for -TAS.…”

Determination of tetracycline, chlortetracycline and oxytetracycline by flow injection with inhibitory chemiluminescence detection using copper(II) as a probe ion

“…Some transition metal ions, such as copper(II), cobalt(II) and chromium(III) have catalytic effects on the luminol-H 2 O 2 reaction widely used in conventional analysis (19,20). Our experimental also showed that high and constant CL backgrounds were obtained by the CL reaction of luminol-H 2 O 2 using copper(II), cobalt(II) and chromium(III) as the catalyst ions; however, when the TCs samples were injected into the reaction cell, the inhibitory CL signals were observed only when using copper(II) as the catalyst ion.…”

Capillary electrophoresis microchip coupled with on-line chemiluminescence detection

“…According to the reports on the CL detection in capillary electrophoresis [14,15,21,26,27], there were two key points that decided whether the experiment could be done successfully. One was the reaction dynamics of the CL systems.…”