Study of a metal-coated hollow-fiber membrane electrode for sugar detection by an amperometric detection method

Abstract

A metal-coated hollow-fiber membrane electrode (MCHE) has been applied as a working electrode of an electrochemical detector in high-performance liquid chromatography. In this paper, the structure of the detector was studied for obtaining a high sensitivity and sharp response on a model of electrochemical oxidation of glucose in an alkaline solution. The MCHE has a tubular structure with an inner volume that broadens the output signal peak with a wide distribution of the specimen concentration due to a residual sodium hydroxide solution. An analysis of the dead volume of the present detector revealed that the volume of holes in the membrane wall was almost equal to the inner volume of the electrode. Only the inside metal layer of the MCHE was made active for electrochemical detection in order to reduce the effect of the dead volume of the membrane holes. The detection limit and the half-width of the peak were down to 0.69 pmol and 1.8 s, respectively.