Electrogenerated Chemiluminescence by Saima Parveen Muhammad Sohail Aslam Lianzhe Hu & Guobao Xu

Author:Saima Parveen, Muhammad Sohail Aslam, Lianzhe Hu & Guobao Xu
Language: eng
Format: epub
Publisher: Springer Berlin Heidelberg, Berlin, Heidelberg

A new ECL chip-type detection cell, which could be used for both CE and FIA was constructed by Wang and co-workers [16]. In their design, the chip-type detection cell is easily convertible to CE and FI measurement mode with run-to-run RSDs of less than 2.5 % for both CE and FI measurements in the linear concentration ranges. This design made a contribution in the development of ECL assay for clinical and biological applications. Subsequently, they fabricated another CE–ECL system with a porous joint as electrical connection of CE. This joint was fabricated by etching capillary wall with hydrofluoric acid after the removal of polyimide coat. Because the porous capillary wall allowed the CE current to pass through and there was no electric field gradient beyond that porous section, the influence of CE high electric field on ECL procedure was negligibly reduced, and no added dead volume was created [27]. Same group has reported a series of researches about an integrated ITO electrode-based Ru(bpy)3 2+ ECL detector for a PDMS/glass hybrid MCE device. This MCE–ECL strategy utilizes an ITO-coated glass slide as the chip substrate with a photolithographically fabricated ITO electrode located at the end of the separation channel in a PDMS layer [56].

Microfluidic chip based on CE has attracted extensive attention recently. Its advantages included short analysis time, portability, disposability, and minute sample and reagents consumption. Moreover, the integration of sample-handling, separation, and detection makes the chip CE system much simplistic and user-friendly. In 2003, the first report about an integrated indium tin oxide electrode-based Ru(bpy)3 2+ ECL detector for a PDMS microchip CE device was presented which describes an indium tin oxide electrode based Ru(bpy)3 2+ ECL detector for a microchip CE. The microchip CE–ECL system consists of a PDMS layer which contains separation and injection channels and an electrode plate with an ITO electrode made by employing photolithographic method. Photon-capturing efficiency is greatly enhanced by binding PDMS layer reversibly to the ITO electrode plate, which greatly simplified the alignment of the separation channel with the working electrode. Moreover, high separation electric field has negligible significant influence on the ECL detector, and decouplers for isolating the separation electric field were not needed in the microchip CE–ECL system. This microchip CE–ECL strategy was successfully applied to proline and tripropylamine as model analytes [24].

In the following year, lincomycin was determined by the microchip CE–ECL system where ITO working electrode was fabricated by photolithographic method from an ITO-coated glass slide (chip substrate) located at the end of the separation channel (Fig. 5.10). The top layer made up of a poly(dimethylsiloxane) (PDMS) layer consisting of two channels, namely separation and injection channels. This microchip CE–ECL system can be successfully applied for the rapid analysis of lincomycin, a tertiary amine, within 40 s in a urine sample without pre-treatment. Linear range of 5–100 and the LOD of 3.1 were obtained with correlation coefficient of 0.998, respectively, under the optimized conditions. This strategy does not need decoupler for isolating the high separation electric field because the influence of the high separation voltage on the ECL signal was negligible.

Download

Copyright Disclaimer:
This site does not store any files on its server. We only index and link to content provided by other sites. Please contact the content providers to delete copyright contents if any and email us, we'll remove relevant links or contents immediately.