SU1571496A1 - Method of producing plates for thin-layer chromatography - Google Patents

Abstract

The invention relates to analytical instrumentation and can be used in the chemical, pharmaceutical and other industries in the manufacture of thin plates for the study of mixtures of complex substances. The purpose of the invention is to improve the analytical capabilities of the plate. A dispersed sorbent layer is deposited on a metal or glass substrate. The plate is dried and placed in a plasma-chemical reactor. The reactor is evacuated and filled with octamethyltrisiloxane vapor. A high-frequency discharge is excited and maintained in the reaction space. As a result, the sorbent layer is covered with a polysiloxane film. The formation of a polysiloxane film causes a change in the sorption dynamics due to clogging of the pores of the sorbent, which reduces diffusion blurring. The use of polysiloxane makes it possible to obtain reverse-phase plates with a chemically and mechanically strong uniform layer that provides advantages in operation compared with reverse-phase plates of other types. 2 tab.

Description

The invention relates to analytical instrumentation and can be used in the chemical, pharmaceutical and other industries in the manufacture of thin-layer plates for the study of mixtures of complex substances.

The purpose of the invention is to improve the analytical capabilities of the plate.

The method is carried out as follows.

A dispersed sorbent layer is applied to a metal or glass substrate. The plate is dried and placed in a plasma-chemical reactor. Reactor

vacuum, let octamethyltrisiloxane vapor in it to a pressure of 10-10 torr, ignite and maintain a high-frequency electrical discharge.

ate 1

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SO About

Example. The Silufol plate was placed on the substrate holder of the plasma-chemical reactor. The reactor was evacuated to a pressure of 10 Torr, filled with octamethyltrisiloxane vapors. In the reaction space, an inductive RF discharge was excited and maintained (frequency 13.56 MHz). The process lasted 10-15 minutes.

The application of a polysiloxane to the sorbent layer results in the hermetic clogging of the pores of the sorbent, leaving it to the surface. As a result, these pores do not contribute to diffusion smearing, and the selectivity of the sorbent remains unchanged. Crosslinking the polysiloxane film with the surface of the sorbent allows the production of reusable plates. Plasma chemical application of polysiloxane from octamethyltrisiloxane vapor provides chemical purity, structural homogeneity of the applied layer, and processability of the plate manufacturing process.

Polysiloxane, being a material mechanically and chemically strong, does not enter chemical reactions with the components of the eluted sample, which excludes the appearance of non-linearity of the isotherm of excessive adsorption as the eluent moves along the plate.

To investigate the analytical capabilities of the plate, the separation of various classes of biologically active compounds was carried out: barbiturates and opium alkaloids, steroid compounds (androgens).

In tab. Figures 1 and 2 present the separation data for the listed biologically active compounds on the plates made by the proposed method and the Silufol plates.

Table 1

The analysis time on the plates installed by the proposed method did not exceed 5 minutes, on known plates it was 10–15 minutes. The selectivity of the proposed plates is higher than in the well-known:

table 2

0

Obtained by repeated elution of codeine 1.33 times; for morphine hydrochloride 1.4 times (for a unit taken R phenolbarbital). The use of the proposed plates leads to a change in the order of output of steroid compounds, which indicates a fundamentally new mechanism for the dynamics of sorption in plates with a second layer of polysiloxane.

Claims (1)

Invention Formula A method for manufacturing a plate for thin layer chromatography, which involves depositing a layer of sorbent on a metal or glass substrate, then drying the plate and processing it by applying an electric discharge plasma in a plasma-chemical reactor, in order to improve the analytical capabilities of the plate, the treatment is carried out to the presence of octamethyltrisiloxane vapor.