Hi to all students of the Laboratory in Biochemistry of 2008.
Here are the compiled results of last year’s lipid standards and some published
Rf values. I have calculated the Rf values of three random groups.
Transfer the graph files to your Word document. Determine the scale of the
X-axis. Use the center of peak 1 as the reference point, and measure the
distance in mm to the centers of the peaks. Then convert to actual distance of
migration according to that scale, and calculate Rf values accordingly.
Lipid standards, instructors’ experiment 2007
The lipid standards were chromatographed in a solvent mixture containing
hexane-diethyl ether-acetic acid [80:20:1]. The plates were dried, stained with
fluorescein, visualized under UV light and the UV-absorbing spots were traced.
TLC was performed in duplicate using two independently prepared solvent
mixtures.
1
2
3
4
6
5
7
8
Phosphatidyl choline
Monoolein
Unidentified diglyceride
Cholesterol
Palmitic acid
Eicosapentaenoic acid
Triolein
Tristearin
Solvent front
mm
0
5
25
29
48
53
91
92
161 mm
Rf
0.03
0.16
0.18
0.29
0.33
0.56
0.57
mm
0
5
25
30
47
55
90
94
168 mm
Rf
0.03
0.15
0.18
0.29
0.33
0.54
0.56
Lipid
Rf (a)
Acceptable Rf values for 2008
1
Phospholipids
0
0
2
Monoglycerides
0.02
0.02-0.08
3
Diglycerides
0.15
0.12-0.15
4
Cholesterol
0.19
0.17-0.22
5
Fatty acids
0.39
0.28-0.35
6
Triglycerides
0.61
0.5-0.7
7
Cholesterol esters
0.94
0.8-0.84
(a) Rf values of lipid standards that were separated in a system identical to that
used by us. Boyer JM, D'Antonio LE, Schiavone WA. Lipid composition and activity of a lytic
factor isolated from Plasmodium berghei. Infect Immun 25:805-809, 1979.
We enjoyed you as students.
Adar, Anat, Aviv, Celeste, Iris, Gideon, Michal, Mirit, Roei, Shelly, Shira and Avi.