Thin layer chromatography (TLC) (Principle, procedure steps, visualisation and applications)

Поделиться
HTML-код
  • Опубликовано: 1 окт 2024
  • This video describes the thin layer chromatography (TLC) technique. It explains the separation process, where the different components present in the mixture. The principle of this method is explained. How various components present in the mixture based on the difference in the affinity between the stationary phase and the mobile phase. Calculation of the retention factor(Rf). List out the advantages and disadvantages is discussed. Various applications of this method is explained. The mechanism of this method is explained. the different methods of visualising techniques is explained. Iodine method, ninhydrin, UV light etc. The calculation of Rf factor i.e retention factor is explained. How different components are separated based on the difference in the polarity is explained.
    Thin layer chromatography (TLC)
    You will be able to
    elucidate the principle of thin layer chromatography.
    explain the procedure to separate and identify the components of a mixture by thin layer chromatography.
    discuss the various methods of visualizing the separated components.
    list out the advantages, disadvantages and applications of this technique.
    Principle of Thin layer chromatography
    Thin layer chromatography (TLC) is a technique used to identify the components/compounds present in a mixture by separating them using a thin stationary phase (silica gel) supported on an inert substrate and a mobile phase (solvent).
    Stationary phase - silica gel, alumina etc. over glass/metal plate, plastic sheet etc.
    Silica gel - acidic - steroids, amino acids, hydrocarbons etc.
    Alumina - basic - amines, bile, lipids etc.
    Cellulose - neutral - carbohydrates, sugars etc.
    Mobile phase - developing solvent/mixture of solvents (reasonably volatile)
    Sample - sample containing mixture of compounds and/or individual compounds
    Silica gel - acidic - separation follows adsorption mechanism.
    Spotting - spot the samples/references using a capillary tube/micropipette on the line drawn 1cm above the bottom
    Developing - developing solvent should be below the level of spotted samples.
    mixtures of strongly polar compounds
    polar compounds -10% methanol in DCM
    strongly basic components -10% NH4OH in methanol in dichlormethane
    Visualisation :
    coloured samples - Just dry to vapourise the solvent
    uncoloured samples
    Iodine chamber - place iodine crystals in the chamber
    Fluorescent substance added to stationary phase (silica gel), which will fluoresce/glow in UV light leaving the dark spots.
    Advantages of Thin layer chromatography
    Disadvantages of Thin layer chromatography
    Applications of Thin layer chromatography

Комментарии • 38