Elimination of glucose interference and improved precision in a continuous-flow analysis for inulin

A modified fermentation procedure based on one described by Homer Smith in his textbook was used to eliminate glucose interference in the automated detrmination of inulin. The manifold of Fjeldbo and Stamey [J. Lab. Clin. Med. 72, 353 (1968)] was modified to enable us to insert the fermentation procedure without sacrificing precision in continuous-flow analysis for inulin. Analytical recoveries of inulin from plasma and urine with the modified manifold were 100.1 +/- 0.8% (SD) and 99.9 +/- 1.6%. Corresponding recoveries of inulin from specimens of plasma and urine containing 5 g of glucose per liter and treated with yeast were 99.6 +/- 1.5% and 100.0 +/- 1.6%.