Science & Technology
Tests for Lipids (Preliminary Test and Confirmatory Test)
Tests for Lipids
Preliminary Tests for Lipids
| Test | Experiment | Observation | Conclusion/Result |
Spot Test |
Poured one or two drops of original solution with the help of a dropper on a filter paper and allowed it to dry. | A fine greasy spot appeared on the filter paper | Lipids are present |
Heating |
Slowly heated 2-3 ml of original solution in a test tube. | No precipitate formation | Proteins are Absent |
Iodine Test |
Took 2-3 drops of original solution and then added a few drops of iodine solution. | The solution does not turns its color | Carbohydrates are absent |
Confirmatory tests for Lipids
| Test | Experiment | Observation | Conclusion/Result |
Sudan III |
2-3 ml of original solution in a test tube and add 3 ml of water then add few drops of Sudan III reagent. Shake properly and allow the solution to stand. | Formation of a red layer on the surface of solution in test tube | Lipids are present |
Oil Emulsion Test |
2.5 ml of O.S. added 2.5 ml of absolute alcohol and then added 5 ml of cold water. Then shake the mixture and allowed it to stand. | A white colored cloudy suspension (emulsion) is formed | Lipids are confirmed |
By Prof. Imran Khan
