Abstract: Reversed phase solid silica gel sorbent layers which can adhere with appropriate binders to a solid surface were developed. Pre-coated RP-rotors of different thickness were used These pre-coated RP-rotors can be used for Centrifugal Preparative Thin-layer Chromatography (CPTLC) using any appropriate device for Centrifugal Chromatography, like Chromatotron® or Cyclograph. Organic compounds including very polar ones can be separated and/or purified in a preparative scale from mixtures by these pre-coated RP-rotors, using different solvent systems. Also described is a new chromatographic separating device (hereinafter Chromato Rotor) and a method for separation of constituents from natural products or mixture of organic compounds using a centrifugal preparative chromatographic instrument with a separating element which contains a binder free sorbent layer packed or loaded between two supporting rotors and retained from moving outside by a porous filter. Only eluants pass through.