Identification of α-Amino Acids by Paper Chromatography (CAT#: STEM-CT-2857-CJ)
Introduction
α-Amino acids are simple molecules that are made of a central C-atom, labelled Ca, that is bound to a primary amine group NH2 and to a carboxylic group COOH.
Paper chromatography principle involved can be partition chromatography or adsorption chromatography. Partition chromatography because the substances are partitioned or distributed between liquid phases. The two phases are water held in pores of the filter paper and the other phase is a mobile phase which passes through the paper. When the mobile phase moves, the separation of the mixture takes place. The compounds in the mixture separate themselves based on the differences in their affinity towards stationary and mobile phase solvents under the capillary action of pores in the paper. Adsorption chromatography between solid and liquid phases, wherein the solid surface of the paper is the stationary phase and the liquid phase is the mobile phase.
Applications
Biochemistry
Procedure
1. Selecting a suitable type of development: It is decided based on the complexity of the solvent, paper, mixture, etc. 2. Selecting a suitable filter paper: Selection of filter paper is done based on the size of the pores and the sample quality. 3. Prepare the sample: Sample preparation includes the dissolution of the sample in a suitable solvent (inert with the sample under analysis) used in making the mobile phase. 4. Spot the sample on the paper: Samples should be spotted at a proper position on the paper by using a capillary tube. 5. Chromatogram development: Chromatogram development is spotted by immersing the paper in the mobile phase. 6. Paper drying and compound detection: Once the chromatogram is developed, the paper is dried using an air drier. Also, detecting solution can be sprayed on the chromatogram developed paper and dried to identify the sample chromatogram spots.
1. It is a low-cost way to separate dissolved chemical compounds based on distinct migration speeds across sheets of paper. 2. Large quantity of sample cannot be applied on paper chromatography. 3. Less Accurate compared to HPLC or HPTLC. 4. Volatile or complex substances cannot be separated using paper chromatography techniques.