Abstract

A combination of the polysaccharide ethyl-hydroxyethyl-cellulose (EHEC) and the surfactant sodium-dodecylsulphate (SDS) has the extraordinary physical property of being liquid at room temperature but gelling firmly at 37 degrees C. It has been named 'liquid fibre' and its effect on gastric emptying has been tested in rats and humans, as well as its effect on intestinal distribution in rats. Rats were gavaged with 5 ml of radiolabelled liquid fibre, SDS in water, or water control. Subgroups were killed after 25, 50, 100, 200, and 300 minutes, the gut removed, and the distribution of radioactivity measured scintigraphically. Liquid fibre gelled in the stomach and spread exponentially down the small intestine before 25 minutes. This distribution was maintained for 200 minutes after which the stomach began to empty again. In the human study, 10 healthy men drank 250 ml liquid fibre and placebo labelled with 1.85 MBq technetium tin colloid on separate occasions. Gastric emptying was measured by gamma-camera. Half emptying time significantly increased from 17.7 to 55.8 minutes (means, p < 0.05). The time for 10% to empty (which includes any lag time) increased from 7.0 to 19.4 minutes (p < 0.05). Average emptying rate decreased from 4.49%/min for placebo to 1.60%/min for liquid fibre (p < 0.01). The dramatic delay in gastric emptying suggests liquid fibre may have clinical applications while its liquid formulation should improve acceptability.