Tourtellotte, W. W., F. M. Parker, and 

 R. N. Dejong 



1958. A study of lipids in the cerebro- 

 spinal fluid, ni. The determination of 

 total phospholipids. Journal of Labora - 

 tory and Clinical Medicine, 52 : 491- 

 495. 



The method is based on co -precipitation 

 of proteins and lipids, determination of 

 phosphorus on an aliquot using HCIO4- 

 H2SO4 for ashing, and colorimetric meas- 

 urement of molybdate color developed with 

 ascorbic acid as reducing agent. The meth- 

 od is capable of determining 0.7 m^moles 

 (0.02^g.) of phospholipid with coefficient 

 of variation of about 5%. 



Tourtellotte, W. W., B. A. Skrentny, and 

 R, N. Dejong 



1959. Lipides in the cerebrospinal fluid. 

 IV . The determination of free and total 



■ cholesterol. Journal of Laboratory and 



Clinical Meditine, 54: 197-206. 

 A method is described for determination 

 of cholesterol in 0.25 ml. of cerebrospinal 

 fluid. The proteins and lipids are co -pre- 

 cipitated with trichloracetic acid and the 

 lipids are extracted from the precipitate. 

 Total cholesterol is determined fluoromet- 

 rically by the procedure of Albers and 

 Lowry ( Analytical Chemistry, 27: 1829, 

 1955) and free cholesterol by a modifica- 

 tion of the Sperry and Webb method (Jour- 

 nal of Biological Chemistry , 187 : 97, 1950). 

 The method is capable of determining 1 ug. 

 of free cholesterol and 0.5^ g. of total 

 cholesterol with variations of 3 and 7%, re- 

 spectively. 



Trappe, W. 



1938. Modification of the Kaufmann meth- 

 od for determining the iodine number 

 for very small amounts of fat. Bio- 

 chemische Zeitschrift, 296 : 180-185. 

 Chemical Abstracts, 33: 420^(1939). 

 The fat (0.2 to 2.0 mg.) is dissolved in 

 CHCI3, brominated with Br2 in MeOH, and 

 titrated iodometrically. 



Trappe, W. 



1940. Separation of biological fats from 

 "At natural mixtures by means of adsorp- 



tion columns. I. The eluotropic series 

 of solvents. Biochemische Zeitschrift, 

 305:^ 150-161. ~ 

 (1941). 



Chemical Abstracts, 35: 



477*^ 



The "eluotropic series" (solvents arranged 

 according to their eluting power) is given. 



Trappe, W. 



1940. Separation of biological lipides 

 from their natural mixtures by adsorp- 

 tion columns. II. Isolation of phospho- 



. rus- and nitrogen-free lipide fractions. 



Biochemische Zeitschrift, 306: 316- 

 336. Chemical Abstracts, "35:2169^ 

 (1941). 

 The relative adsorbabilities of lipid frac- 

 tions from biological materials are listed. 



Trappe, W. 



1941 . Separation of biological lipides 

 from their natural mixtures by means 

 of adsorption columns . III. Separation 

 of phosphorus- and nitrogen-free lipide 

 fractions . Biochemische Zeitschrift, 

 307: 97-106. Chemical Abstracts, 35: 

 40533(1941). 



Free fatty acids with phosphatides were 

 separated from total lipid extract on an 

 Al20q column . An activated Frankonite KL 

 column was used to separate hydrocarbons 

 and cholesterol esters. 



Trappe, W. 



1942. Determination of free and ester- 

 ified cholesterol in . 1 cc . blood from 

 the finger tip. Klinische Wochenschrift, 



" 2j.: 651-652. Chemical Abstracts, 38: 



2058^(1944). 

 Blood lipids are adsorbed on 5102- Ester- 

 ified cholesterol is eluted with benzene, free 

 cholesterol is eluted with Et20-CHCl3, the 

 solvents are evaporated, and cholesterol is 

 estimated in each fraction with AcOH-ZnClo 

 and AcCl. 



Trappe, W. 



1943. Simple method for the separate 

 quantitative estimation of free and 

 esterified cholesterol in blood serum 



■ without digitonin precipitation and sapon- 



ification . Zeitschrift fiir physiologische 

 Chemie, 273:177-190. Chemical Ab- 



70 



