The amperometric determination of glucose can be performed using a flow injection system with a wall-jet flow-through cell and a graphite paste electrode. The working electrode is prepared from a mixture of graphite powder, silicone oil and glucose oxidase and exhibits a linear response in a single-line manifold for glucose concentrations up to 30 mM with a sampling rate of 120 samples per hour. The detection limit calculated for a 750-µl sample volume injected is 20 µM glucose. The average lifetime of the developed sensor is 3 weeks without a significant decrease in sensitivity.