Separación de pigmentos vegetales por cromatografía en papel

Photosynthetic Pigments and Paper Chromatography

Introduction to Photosynthetic Pigments

• The practice focuses on separating and identifying photosynthetic pigments from various plant species using paper chromatography.

• Chloroplasts contain chlorophyll, which gives them a green color, but they also include other pigments like carotenes and xanthophyll.

Types of Plant Pigments

• Different pigments are identified:

• Intense green chlorophyll

• Green chlorophyll

• Light yellow carotenes

• Orange-yellow xanthophyll

• Each pigment has a unique chemical structure that influences its absorption of specific wavelengths of light.

Technique Overview: Paper Chromatography

• Paper chromatography is a technique that allows for the separation and detection of reaction products, revolutionizing compound identification since 1944.

• The method relies on the varying solubility of plant pigments in organic solvents versus water, facilitating their separation as they move through filter paper.

Materials Required for Experimentation

• Essential materials include:

• Fresh leaves (e.g., calla, spinach)

• Mortar and pestle

• Glass funnel, beaker, capillary tube, pipette

• Solvents such as acetone or ethyl alcohol

Experimental Procedure Steps

• Clean fresh leaves with distilled water before cutting them into small pieces for extraction.

• Combine leaf pieces with sand and acetone in a mortar to create a homogeneous mixture.

• Filter the mixture through prepared filter paper to obtain vegetable pigment solutions.

Observations and Conclusions from Chromatography Results

• After applying the solution onto filter paper, distinct bands representing different pigments are observed based on their mobility.