A more sensitive and stable colorimetric determination of free fatty acids in blood.

A sensitive method is proposed for the colorimetric determination of free fatty acids (FFA). Diphenylcarbazide containing diphenylcarbazone is used as the color developing reagent instead of diethyldithiocarbamate which was employed in the previous method (1965). J. Lipid Res. 6: 16-20). The present method was successfully applied to the determination of FFA present in as little as 40 microliter of whole blood.