A JET RING CELL WITH A RENEWABLE SOLID SUPPORT FOR AMPEROMETRIC DETECTION OF GLUCOSE IN A SEQUENTIAL INJECTION-ANALYSIS SYSTEM

A new amperometric method for the detection of glucose has been develo ped. A jet ring cell with a renewable solid support (JRR) is connected to a sequential injection analysis (SIA) system. The solid support, c onsisting of small spherical particles of agarose gel, with a mean bea d size of 90 mu m, is coupled with the enzyme glucose oxidase (GOD). T he suspension is injected through a multiport valve in the SIA-system and is trapped in the JRR cell by a gap of 10 mu m between the glassy carbon (GC) working electrode and a stainless steel counter electrode. The subsequent injection of glucose results in formation of hydrogen peroxide, which is detected by oxidation at 1.0 V (vs. Ag/AgCl/KCl (3 M)), Thereafter the suspension is removed by reversing the pump flow a nd subsequently replaced with fresh suspension for the next determinat ion of glucose, The Linear working range for the JRR-sensor, at this s tage of the work, is 100 mu M - 5 mM.