Which of the following is a planar chromatography method?

• A. Paper chromatography
• B. HPLC
• C. GLC
• D. GC-MS

Answer: (A)

Planar chromatography means separation on a flat surface, where the stationary phase is spread over the surface and the mobile phase moves across it in two dimensions. Paper chromatography is a classic example because the sample is spotted on paper and the solvent travels up the flat sheet by capillary action, separating components along the plane of the paper. The other methods rely on a column—packed or coated—through which the mobile phase flows, so they are column chromatography, not planar. Gas chromatography and its coupling with MS also separate compounds inside a column and are not planar. Therefore, the planar chromatography method among the options is paper chromatography.