A porous layer open tubular (PLOT) column includes capillary tubing; one or two particle traps disposed inside one or two end sections of the capillary tubing; and a stationary phase comprising a porous or non-porous material coated inside a main section of the capillary tubing. A method for preparing a porous layer open tubular (PLOT) column includes preparing one or two particle traps inside one or two end sections of a capillary tubing; and preparing a stationary phase comprising a layer of a porous material coated inside a main section of the capillary.