A Description of Leibermann Burchard Test
Leibermann-Burchard Test
i. Objectives: To determine the presence of unsaturated sterols, in this test, cholesterol in the given sample. ii. Results
Sample
Observations
Residue C
Blue green solution
Vegetable Oil
Emerald Green solution
iii. Discussion
Cholesterol is a member of a large group of substances called steroid, which include vitamin D. Cholesterol is an essential component of cell membrane, brain and nerve cells, and bile, which helps the body absorb fats and fat soluble vitamins. The body uses cholesterol to make vitamin D and various hormones, such as estrogen, testosterone, and cortisol. The body can produce all the cholesterol that it is needs, but it also obtains cholesterol from food.
Lieberman-Burchard test: The Lieberman-Burchard or acetic anhydride test is used for the determination of cholesterol. The formation of a green or green-blue color after a few minutes is positive. Lieberman-Burchard is a reagent used in a colorimetric test to detect cholesterol, which gives a deep green color. This color begins as a purplish, pink color and progresses through to a light green then very dark green color. The color is due to the hydroxyl group (-OH) of cholesterol reacting with the reagents and increasing the conjugation of the unsaturation in the adjacent fused ring. Because this test uses acetic anhydride and sulfuric acid as reagents caution must be exercised so as not to receive severe burns.
In this experiment, two clean and dry test tubes were prepared with test tube 1 containing dissolved Residue C in methylene chloride and test tube 2 with 1.0 mL vegetable oil. 5 drops of acetic anhydride was added, followed by 3 drops of concentrated sulfuric acid into both test tubes and were mixed thoroughly.
Principle: Oxidation. This test is used in the estimation of blood cholesterol. Cholesterol produces a characteristic green color when it is mixed with the Liebermann-Burchard reagent, a mixture of acetic anhydride and sulfuric acid. The change in
i. Objectives: To determine the presence of unsaturated sterols, in this test, cholesterol in the given sample. ii. Results
Sample
Observations
Residue C
Blue green solution
Vegetable Oil
Emerald Green solution
iii. Discussion
Cholesterol is a member of a large group of substances called steroid, which include vitamin D. Cholesterol is an essential component of cell membrane, brain and nerve cells, and bile, which helps the body absorb fats and fat soluble vitamins. The body uses cholesterol to make vitamin D and various hormones, such as estrogen, testosterone, and cortisol. The body can produce all the cholesterol that it is needs, but it also obtains cholesterol from food.
Lieberman-Burchard test: The Lieberman-Burchard or acetic anhydride test is used for the determination of cholesterol. The formation of a green or green-blue color after a few minutes is positive. Lieberman-Burchard is a reagent used in a colorimetric test to detect cholesterol, which gives a deep green color. This color begins as a purplish, pink color and progresses through to a light green then very dark green color. The color is due to the hydroxyl group (-OH) of cholesterol reacting with the reagents and increasing the conjugation of the unsaturation in the adjacent fused ring. Because this test uses acetic anhydride and sulfuric acid as reagents caution must be exercised so as not to receive severe burns.
In this experiment, two clean and dry test tubes were prepared with test tube 1 containing dissolved Residue C in methylene chloride and test tube 2 with 1.0 mL vegetable oil. 5 drops of acetic anhydride was added, followed by 3 drops of concentrated sulfuric acid into both test tubes and were mixed thoroughly.
Principle: Oxidation. This test is used in the estimation of blood cholesterol. Cholesterol produces a characteristic green color when it is mixed with the Liebermann-Burchard reagent, a mixture of acetic anhydride and sulfuric acid. The change in