Stationary Support:

As mentioned already, the stationary support material is a highly purified cellulose filter paper like Whatman No. 1, 2, 31 or 3 MM or acetyl acid paper having hydrophilic affinity for water. A solvent penetrates the fiber and causes swelling of paper modify its dimensions. Polymeric cellulose structure holds various thousand anhydroglucose units linked by oxygen atoms. Alternatively, modified forms of paper such as impregnated with alumina, silica gel, hydrous zirconium oxide, ion exchange resin may be used. Manytimes paper is coated with chelating agent solution such as dimethylglyoxime, 8-hydroxyquinoline and many more. However, it should not have any impurities of Ca²⁺, Mg²⁺, Fe³⁺, Cu²⁺ etc so as to avoid interference. The paper is impregnated either neat or dissolved in a volatile solvent. The solvent should evaporate slowly so that stationary phase may distribute homogeneously. In this case, coated liquid phase may interfere with the detection of separated spots. The paper shows following properties:

1. Weak ion-exchange properties

2. Adsorptive properties

3. Water holding property

4. Mild reducing agent

The quality of paper and its porosity play an important role in paper chromatography as it determines the rate of movement of the solvent used. Thick paper with increased sample capacity may be used for preparative studies. The most suitable cardboards are Schleicher and Schull 2070, SS2171 that could take a load up to 1 g at each point of application. Generally, a paper strip is cut into 4 cm × 30 cm for one dimensional PC. For two dimensional PC, however, a 30 cm × 30 cm square sheet is commonly used.