Types of Papers and their applications in Paper Chromatography

Papers for Chromatographic Separations (Image Courtesy : www.webshop.fishersci.com)

Paper chromatography makes use of paper which acts as a stationary phase. Paper essentially consists of cellulose fibers which are polymers having – OH functional groups sticking out of the polymer chains. These groups lead to retention and separation of surface absorbed molecules. In practice the separating molecules equilibrate between the layer of adsorbed water and the mobile phase solvent.

Different types of paper have been tried but Whatman No1 and 3 filter papers are found more suitable for analytical work. Chromatography paper is commonly available as 18”X22” rectangular sheets. Apart from Whatman other popular manufacturers of chromatographic paper are Schleicher and Schull, Macherey Nagel, and Eaton-Dikeman but Whatman appears to be a popular choice.

Choice of Paper

Coarseness of the fibers and packing density of papers decides between speed and resolution. Fast papers are useful for major applications and when high resolutions are necessary slow papers are preferred

Examples of Whatman filter paper

Fast Medium Slow
No 4 No 7 No 2
No 17 No 3 and 3 MM

Modified papers

In addition to pure cellulose several modified versions are also available to meet the specific separation requirements which include acetylated papers, silicone oil impregnated papers, silica and alumina impregnated papers and papers impregnated with ion exchange materials. Some typical applications of modified papers are

Type of paper Typical applications
Ion exchange papers Charged molecule or ionic separations
Silica or Alumina impregnated papers low polarity molecules such as amines steroids, fatty acids, vitamins and pesticides
Acetylated papers insecticides, pigments and metal
Carboxylated papers cationic separations of proteinated
amines and amino acids
About Dr. Deepak Bhanot

Dr Deepak Bhanot is a seasoned professional having nearly 30 years expertise beginning from sales and product support of analytical instruments. After completing his graduation and post graduation from Delhi University and IIT Delhi he went on to Loughborough University of Technology, UK for doctorate research in analytical chemistry. His mission is to develop training programs on analytical techniques and share his experiences with broad spectrum of users ranging from professionals engaged in analytical development and research as well as young enthusiasts fresh from academics who wish to embark upon a career in analytical industry.

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