Keiichiro Sugimoto

CHAPTER 27:Assays of Fructose in Experimental Nutrition

Fructose concentrations in body fluids may be important in research on diabetes and its complications, semen, and absorption and metabolism of fructose. Determination of low concentrations of fructose in body fluids is difficult because coexisting substances interfere with the sensitivity of assay systems. Many methods have been developed using colorimetric reagents, specific enzymes for fructose, high performance liquid chromatography (HPLC), and gas chromatography/mass spectrometry (GC/MS). Chemical methods using colorimetric reagents and enzymatic methods have low sensitivity for fructose but are simple and inexpensive to perform. They are applied to specimens containing high concentrations of fructose (over 100 μM), such as blood after fructose or sucrose tolerance tests, seminal fluid, and fructose-containing media. HPLC and GC/MS methods can concurrently measure fructose and other polyols with high sensitivity and accuracy (over 20 μM and 1 μM, respectively), but require expensive and sophisticated instrumentation. They can be applied to various types of sample, e.g., urine and peripheral blood in the fasting state, and several tissues such as the lens in experimental models of diabetes.