FIELD: chromatographic analysis. SUBSTANCE: process of detection and/or quantitative analysis with use of planar chromatography involves chromatographic separation in chamber. Chamber has chromatographic plate with deposited layer of sorbent. Stepped decrease of pressure is created in separation chamber. Device for realization of invention includes separation chamber with chromatographic plate, aids for tight encapsulation of mentioned plate and aid to decrease pressure in named chamber. Aid to decrease pressure is connected to aid of adjustment of gradient of decreased pressure. Aid for tight encapsulation of plate is hydrophobic membrane. Technical result of invention consists in exclusion of preliminary preparation of chromatographic plate and of propagation of steamlike phase. EFFECT: exclusion of preliminary preparation of chromatographic plate and prevention of propagation of steamlike phase. 3 cl, 5 dwg, 1 tbl
