Determination of free fatty acids in human bile by high-performance liquid chromatography

We developed a high-performance liquid chromatography (HPLC) method for free fatty acids (FFAs) analysis in bile. In this method, FFAs were extracted from bile in a single step using an Isolute ODS cartridge, derivatized with 9-anthryldiazomethane (ADAM). ADAM was chosen because of its high reactivity with carboxylic acid at room temperature. Then, HPLC was used for separating and quantifying FFAs. This method proved to be simple and time-saving. The mean recovery of FFA added to human gallbladder bile was 97.6%, and the detection limit was 100-250 pg. Using this method, we determined FFA concentrations in the gallbladder bile of 11 gallstone patients. The mean concentration of total FFA was 0.61 (SD = 0.41) mmol/L, and there was wide variation in the individual FFAs.