CS228646B1 - Moving column cap for liquid chromatography - Google Patents

Abstract

The movable column cap is designed for industries where liquid chromatography is used. The essence of the movable cap, consisting of a cap body made of stainless steel, on which radial notches are made for liquid distribution, a supply capillary welded to the cap body and a polytetrafluoroethylene piston, is that the polytetrafluoroethylene piston is deformed in the column by a pressure nut and a centric tube. The movable column cap for liquid chromatography can be used in liquid chromatography in chemical and biochemical laboratories and test rooms.

Description

2,228,648

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a movable column closure for liquid chromatography.

Column closures for liquid chromatography / terminals, end sections / hold the column charge in place and provide controlled solvent flow, eluent to column and column. Column closures are required to seal the column at working pressure, withstand the chemical and thermal conditions of the experiment, ie, aqueous and organic eluents, salt solutions, weak acids and alkalis as well as solutions of the heaviest analytes in the temperature range according to the type of separation from -10 ° C to 100 ° C and in some cases even more · When separating biological materials, the column closures must be sufficiently inert to be non-denatured · The closures must be designed in such a way that the small minimum free, unfilled areas in order to there was no mixing of the turbulence at the liquid flow and the handling and the simplest of them. These technical parameters are in practice associated with economic requirements. An example of sealing the plungers of syringes is described in FIG. 153 226. Generally, the liquid chromatography columns are divided into solid / stationary / movable · Moving closures are used primarily in conjunction with translucent glass or honeycomb columns when the column load tends to change in volume during the experiment. Thus, the problem is the sealing of the movable piston closure with respect to the walls of the column. The easiest way to achieve this is to seal the closure caps 228 848 by means of a ring or rings made of 2. elastomers. Such sealing rings are deformed when the piston closure is inserted into the column, or the closure is designed so that the sealing rings are pressed against the column wall by a special means. However, this solution is only suitable for aqueous eluents or a small range of organic solvents. with extreme polari- ties »The use of high-resistance fluorocouplers is a certain improvement. Materials of this type are not, however, universally resistant and expensive. Further improvements have been made using the combined sealing rings, the inner part of which is made of elastomers, and the surface film is & polytetrafluerethylene. Polytetrafluoroethylene is resistant to all chemicals and is also sufficiently heat resistant, but not very flexible. The disadvantage of said combined sealing rings is that, apart from the high price, the surface film made of polytetrafluoroethylene, which has to be very thin, will damage Xahkosa as a result of the sealing. there is a danger of an accident which is particularly pronounced in the case of non-continuous working equipment such as conventionally liquid chromatographs and also in the use of flammable, explosive and toxic organic solvents. the sealing element of the movable rubber closure is a thin-walled piston made of polytetrafluoroethylene, which is pressed from the inside by rubber rings on the inside · However, the disadvantage of these closures is their higher design intensity. o that the aggressive eluent can get. thin-walled piston and disrupt rubber rings

The above-mentioned drawbacks are eliminated by the movable closure of a liquid chromatography wheel consisting of a stainless steel body closure, which radially cuts the liquid distribution from the inlet capillary welded on the closure body and the polytetrafluoroethylene piston according to the invention, the polytetrafluoroethylene the piston is deformed by a column with a pressure nut and a centric tube ·

The invention of the movable column closure for liquid chromatography allows sealing also in organic solvents and at elevated temperatures.

The movable column closure of the liquid chromate is schematically illustrated in the attached drawing.

The eluent is fed through the feed capillary 3 to a stainless steel housing 4 which is made of stainless steel. The inlet capillary 3 and the cap body 4 are welded together. Radial notches for fluid distribution are formed on the telescopic closure 4.

On the body of the closure 4 there is a mandrel 6 and a welded or screwed tube 2 to be threaded on it. In another case, the tube 2 and the body of the closure 4 are made of one stainless steel scythe · The body of the closure 4 has a diameter of 0.1 mm smaller than the diameter of the column and the diameter of the sealer made of polytetrafluoroethylene. In the seal 5 of the piston 5, notches are inserted into which the mandrels 8 and 6 engage to prevent the piston 5 from rotating. 1 which is formed on the lower portion of the mandrel and on the upper portion to be held by hand. The pressure of the pressure concentric tube X on the sealing piston is formed by the tightening of the pressure nut 2 on the thread of the tube 2 »The pressure nut 7 is shaped to be easily gripped? and rotate?

The displacement of the sealing piston 5 made of poly-tetra-fluoroethylene, which can be achieved by manually pulling the pressure nut 7 against the center tube 1, sufficiently elutes the eluents to pressures of 1-2 MPa, which are used in conventional liquid chromatography. But deformability? polytetrafluoroethylene is not large · Is it necessary to use the colony design? glass tube and accurate diameter. Alternatively, where the contact of the eluent (s) of the analyzed sample (s) and the non-corroding whole, the capsule body (11) and the hard plastics tube (2), such as polyamide, polymethyl methacrylate or polycarbonate, are to be avoided. Polytetrafluoroethylene feed capillary 3 is attached to the end of tube 2. In this case, the non-shut off volume of the cap is loosened and the sealing properties are halved · 228 646 In cases of extremely sensitive or aggressive systems, the cap body 4> tube 2 and seal 5 may be constructed a single piece of polytetrafluoroethylene, while the saop reduces the sealing properties of the cap ·

The invention of the movable closure of a liquid chromatography column can be used in liquid chromatography, chemical and biochemical laboratories and testing laboratories.

Claims (1)

A movable liquid chromatographic column seal comprising a seal body made of stainless steel on which radial indentations are provided for distributing liquid from an inlet capillary welded to the seal body and a polytetraXluoroethylene piston, characterized in that the polytetrafluoroetone is (polytetrafluoroetone). deformed in column by pressure nut (7) and pressure centric tube (1) ^ 1 drawing