Sorbitol dehydrogenase (E.C. 1.1.1.14) is immobilized chemically on poly(vinyl alcohol) beads and used as a column reactor in a liquid chromatographic system for the specific detection of D-xylitol, D-sorbitol and D-ribitol. The alditols are separated from each other on a TSK gel SCX (5-mu-m, Ca2+ form) column (30 cm x 7.8 mm i.d.) with water as eluent. The NADH produced from the enzymatic reaction is monitored spectrofluorimetrically. Calibration graphs are linear between 2 and 500-mu-M for xylitol, 5 and 800-mu-M for sorbitol and 2 and 500-mu-M for ribitol.