The chromatographic processes in the S-chamber with the counter plate

About Some Specific Features of TLC in an Ultra-Small Volume S-Chamber and a Chamber with a Closed Sorption Layer

“…Separation was implemented in the S min -chamber [3,4] and the O-chamber [5][6][7], and for comparison in the traditional N-chamber, without any previous saturation of the adsorption layer of the plate and of the chamber with mobile phase vapors in this chamber.…”

“…1 the small volume S min -chamber is illustrated, the design concept of which considerably differs from the known chambers of this type; it differs by the distance between the adsorption layer of the plate and the upper cover plate (d). In this chamber the value d makes up only 0.1-0.2 mm, which is of principal significance, as shown by the authors [3]. In the articles and the monographs known to us, this value ranges between 0.5 mm [8], 1-1.5 mm [9][10][11][12][13][14][15] and 5 mm [16].…”

“…This drawback is substantially decreased in a sandwich-chamber (S-chamber). Let us note that a recent study [3] has shown that decreasing the gas volume to a minimal value in an S-chamber substantially decreases the duration of wetting a plate with a mobile phase and increases the efficiency of separation. Earlier, Berezkin and Buzaev [4] proposed carrying out TLC generally in the chromatographic system with a zero external volume (the O-chamber); that is, they proposed carrying out TLC on a plate with a closed sorption layer (TLC-CL).…”

“…Thus, in the literature less than 10% of the publications are devoted to separation with the use of S-chambers. The use of the S min -chamber with the ultra-small distance d proposed by us permits markedly decreasing the duration of plate development (*25%) to increase the chromatographic process efficiency (*15%) [3]. In the O-chamber for TLC, for the time of the experiment a TLC plate is virtually transformed into a flat, rectangular quasi-column [4][5][6].…”

“…1,2), which are insufficiently known and studied: (1) an S min -chamber with an ultra-small gas volume [3,7] and (2) a closed chromatographic system in which there is no gas medium above the adsorption layer of the plate in general [4][5][6]. S-and O-chambers are special types of chambers for TLC that deserve special examination because these chambers permit implementing the chromatographic process in a way that is free of one of the important drawbacks of classical TLC repeatedly noted in the literature [2], i.e., the adverse influence of the volume of the gas coming in contact with the adsorption layer of the plate.…”