Abstract: Factors affecting physical dispersion in flow cells were investigated by using a single-line manifold, consisting of PTFE tubing (110 cm x 0.58 mm), a Rheodyne 5020 sample valve and a Gilson Minipuls 2 peristaltic pump. Tartrazine, employed as a tracer to indicate flow paths, was detected by spectrophotometry. Flow studies on four cells (of volume 0.6, 8.0, 25 and 60 µL) showed that, to minimize dispersion, cell volume should be kept as small as possible, consistent with the requirements of sensitivity and light throughput, and also the cells used should cause minimal disturbance of the carrier stream from the manifold.