Comparison of Macro- and Microgravimetric Technic for Lipid Analysis of Serum. ∗

Abstract

Summary And Conclusions

Studies of the serum fatty acids from a child with a known lipemia (nephrosis) by means of the microgravimetric technic of Wilson and Hansen were made and the values thus obtained compared with those found by using 20 times the amount of fatty material. The results showed the amounts of saponifiable fraction recovered, the titration values, and the calculated molecular weights to be almost identical by both the micro and macro methods. Those obtained for the iodine numbers, however, by the use of the Yasuda micro method were consistently somewhat lower than those obtained by the use of the Hanus method and lower than would theoretically be expected. Dilution of the reagents used in the Hanus method for adaptation to a micro technic, resulted in iodine number values practically identical with those obtained by the Yasuda micro method.

From the data presented it seems warranted to conclude that the microgravimetric is a satisfactory technic for lipid analyses. Although the degree of unsaturation of the lipids tends to be somewhat lower when micro quantities are used, the pyridine sulfate dibromide reagent gives results comparable to the Hanus reagent diluted for adaptation to micro quantities.