‘Stereo-chromatography’: a New Method for Chemical Identification and Preparative Isolation

Abstract

SINCE the initial reports on chromatographic techniques¹, and more especially after the investigations of Consden, Gordon, and Martin², and Martin and Synge³, numerous modifications of these procedures have made possible remarkable advances in biochemical research. By evaluation of migration characteristics of unidentifiable with identifiable solutes separated by partition chromatography, identification of unknown solutes has been made possible. Similarly, by utilizing preparative ‘filter paper pile’ techniques, such as the chromatopile^4,5, the chromatopack⁶, or the chromatoblock⁷, constituents of concentrated mixtures can be chemically resolved to yield semi-micro-quantities of pure materials. The present communication concerns the feasibility of utilizing three-dimensional, compressed, paper-pulp blocks for preparative chemical isolation and identification. This technique has three distinct advantages: (1) It makes possible the analysis of an additional parameter, the ‘spreading factor’ (R_s), which can be used to differentiate chemically constituents of the solute mixture together with conventional R_F values; (2) it offers a support system capable of handling and separating exceptionally concentrated loads of solute mixtures for subsequent semi-micro-determinations; (3) it provides a closed system which should inhibit oxidations or photochemical alterations of solute zones which sometimes occur in conventional paper chromatography. One disadvantage of the technique is that it requires a solid, compressed fibre block, which, although inexpensive to fabricate, is not yet commercially available. In addition, the procedure necessitates the use of an electric band or jigsaw for serial sectioning of the chromatographic block.