Amperometric Detection of Carbohydrates by Capillary Electrophoresis with a Cuprous Oxide Modified Sol-Gel Carbon Composite Electrode

✍ Scribed by Lin Hua; Lian Sai Chia; Ngoh Khang Goh; Swee Ngin Tan

• Publisher: John Wiley and Sons
• Year: 2000
• Tongue: English
• Weight: 743 KB
• Volume: 12
• Category: Article
• ISSN: 1040-0397
• DOI: 10.1002/(sici)1521-4109(20000301)12:4<287::aid-elan287>3.0.co;2-o

✦ Synopsis

A new sensitive electrochemical detector has been developed for the amperometric detection in capillary electrophoresis (CE). Chemically modi®ed sol-gel carbon composite electrodes (CCEs) containing cuprous oxide exhibit a sensitive electrocatalytic response for the oxidation of carbohydrates. The electrochemical pretreatment at 1.80 V (vs. SCE) for 60 s results in a marked enhancement of the current responses for all sugars examined, compared to the untreated electrode. A sample mixture containing 8 different sugars was separated within 30 min at an optimal constant potential of 0.65 V (vs. SCE). The stability of an electrochemically preanodized Cu 2 O-CCE was also investigated in CE experiments. The peak current reproducibility with this preanodized electrode over a period of 10 h was within 5 %. Calibration was linear over the concentration range from 2 to 400 mM with the limits of detection for the carbohydrates studied in the range of 0.75±1.3 mM.