A two‐electrode system‐based electrochemiluminescence detection for microfluidic capillary electrophoresis and its application in pharmaceutical analysis

Abstract

A two-electrode configuration powered by batteries was designed for a microchip capillary electrophoresis-electrochemiluminescence system. A home-made working electrode for end-column mode detection and wall-jet configuration was made up of a platinum wire (0.3 mm diameter) and a quartz capillary (320 µm internal diameter). The platinum wire served as a pseudoreference electrode. The configuration of the detection power supply comprised two D-size batteries (connected in series), a switch, and an adjustable resistor. The microchip consisted of two layers: the bottom layer was a glass sheet containing injection and separation channels; the upper layer was polydimethylsiloxane block. In order to reduce the loss of electrochemiluminescence signal, a coverslip (0.17 mm thickness) was used as the floor of the detection reservoir. The performance of the system was demonstrated by separation and detection of atropine, anisodamine and proline. The linear response for proline ranged from 5 µM to 100 µM (r = 0.9968), and the limit of detection was 1.0 µM (S/N = 3). The system was further applied to the measurement of atropine in atropine sulfate injection solutions with the limit of detection 2.3 µM. This new system is a potential tool in pharmaceutical analysis.

Microfluidics as a Novel Tool for Biological and Toxicological Assays in Drug Discovery Processes: Focus on Microchip Electrophoresis

“…This information is extremely important for the determination of the appropriate dose to reduce the risk of the development of side effects, resulting in better treatment protocols. For example, a two-electrode electrochemiluminescence detection method for ME was developed by Pan et al [52]. Their system was able to separate and detect atropine, anisodamine, and proline with a LOD of 1 µM.…”

Microwave Enthrakometric Labs-On-A-Chip and On-Chip Enthrakometric Catalymetry: From Non-Conventional Chemotronics Towards Microwave-Assisted Chemosensors

“…The so-called generator-collector voltammetry at paired electrode junctions [96] can, with modification and certain additions, be implemented within this task. In this connection, it is worth considering on-chip two-electrode capillary electrophoresis with a platinum wire as a pseudo-reference electrode [97], as capillary electrophoresis is used as a tool for microwave-activated electrochemical detection [98], but at the same time, microwave-activated electrophoresis has not yet been implemented on a chip.…”

Microchip-based electrochemical detection using a 3-D printed wall-jet electrode device

“…Although there are a few reports showing the integration of WJE in microfluidic devices, they used glass microchannels (requiring clean room for fabrication) and the electrode has to be manually aligned with the separation channel since the electrode is separate from the microchip. 21–23 …”

“…Although there are a few reports showing the integration of WJE in microfluidic devices, they used glass microchannels (requiring clean room for fabrication) and the electrode has to be manually aligned with the separation channel since the electrode is separate from the microchip. [21][22][23] As compared to the lithographic-based fabrication of devices, three dimensional (3-D) printing is an attractive approach for device design and creation. 3-D-printing is a rapid prototype technology that can build a 3-D configuration in a "layer-by-layer" process.…”