Materials and Methods

Many of the difficulties encountered in the original Fiske and SubbaRow method for estimating serum phospholid were corrected through the use of vanadium pentoxide, a catalyst used in sample digestion, and through other minor modifications. Results obtained by the modified method agree well with those obtained by three other established phospholipid procedures. The greatly im-proved speed, simplicity, accuracy, and precision now makes the modified Fiske and SubbaRow method ideal for clinical or research use. Over the years, a multitude of phospholipid meth-ods have evolved, that of Fiske and SubbaRow (1) being by far the most frequently used (2), in spite of the fact that it has been criticized for lack of repro-ducibility (3), narrow range of acid tolerance (4), poor sensitivity (5, 6), lack of linearity (7), instability of the final color (8), turbidity formation (8), and for being a time-consuming procedure. I would like to describe a modification of the Fiske and SubbaRow method (1) in which most of the problems listed above are eliminated