Fixing arrangement for chromatography columns

Abstract: New fixing arrangement for chromatography columns, this arrangement showing first retaining means (13, 14) of the column (1) designed to allow the column's manually quick change without the help of any special tools and facilitating the reuse of the input and output nipples of the column(1); and second means (2b) designed to fix and hermetically sealing the connecting nipple (7) of the capillary. The special setting of the column retaining means allows that a pre-column cartridge (10) is included or not, the fucntion of the cartridge being to extend further the column useful life. The pre-column cartridge coupling arrangement also removes the formation of any dead volumes, which presence is critical to any chromatographic separation, all that happening because of the suppression of the coupling fittings between both components.

Description: The present invention relates to a new fixing arrangement for chromatography columns. The high-pressure fluid chromatography columns presently comprise an inner-polished steel pipe with a nipple at each of the pipe ends. These nipples incorporate a microfilter which function is to retain the filling microparticles and which microfilter packaged at high pressure inside said assembly is suitably making up the proper chromatographic substrate accountable for the analytical separation. A known fixing device for analytical columns is disclosed in US-A- 4 636 316. The analytical separation is achieved by pumping the suitable solvent through the chromatographic column, and taking into account the high loading losses caused by these microparticulate fillings (3-10 um), it will then be required to work at pressures which might easily reach a range of 3-4000 psi (1 psi = 6895 Pa). The new chromatography column system, object of the present invention, is providing as regards to the above disclosed presently state of the art, the advantages acquired as listed below. 1. - If an extended use of the column causes the chromatographic filling to be exhausted. it will then only be required to replace the steel pipe containing the filling by another new one, and the column's input and output nipples become thereby as reusable contrary to what is presently happening where the total refuse. either nipples or column is forcefully urged. This advantage provided by the arrangement, object of the present invention, is yielding remarkable savings for the user. 2.- In the replacement of any old cartridge by another new one, the help of any type of tools will not be required since the quick-coupling arrangement has particularly been designed for the chromatographic cartridge. 3.- The concept of the new cartridge-nipple arrangement allows, without requiring any additional fittings, that a cartridge acting as a pre-column can be inwardly coupled there, with the beneficial purpose of lenghtening the column's useful life. 4.- The design of the new pre-column cartridge-coupling arrangement fully removes any formation of dead volumes, which presence might be very critical for any chromatographic separation. The above is achieved because the new design fully removes any requirement of coupling fittings between both components. To facilitate still further the disclosure, the present description is accompanied by drawing sheets, wherein a case of embodiment cited only by way of example is illustratively shown. In the drawings: Figure 1 shows a diametral cross-section of a chromatographic column, wherein said column's retaining means and the connecting nipple's hermetically sealed fixing means can be seen, including a cartridge acting as a pre-column. Figure 2 shows a view similar to the previous one, wherein the arrangement, object of the present invention is shown when the pre-column cartridge is excluded. Returning to the figures, the embodiment of a new fixing arrangement for chromatography columns can be seen there comprising first means designed to retain column -1- and second means designed to fix and hermetically seal the connecting nipple-7-. The column's retaining means are made up with blind housings -13,-14- provided at the column's outside surface and placed at a different level and designed to receive respective spheres -15- located at through-holes drilled in the wall of a column's coaxially tubular body -2- provided with a likely-inverted vessel concentrically wall -2a-which combined with a releasing/retaining bushing -3- sets up a housing for a compressing spring-5- charged with the function of moving along said bushing -3- towards an operating position, only limited by a safety ring -4- which is keeping the assembly duly joined and at which operating position, the axial stress against the spheres -15- is laid down. The change of column -1- is performed without the help of any special tools and exclusively only by means of the body-2- providing the column's quick change by simply axially moving along said body-2-, until the blind holes -16- drilled in the body's inner surface are mated with the spheres-15-. The fixing means of the connecting nipple -7- comprise a knurled nut- 6- allowing said nipple -7- to be fixed to the column -1- both as manually through its outside knurling and as by means of a spanner through its fixing planes. Said unit is associated to the body-2- by the threaded portion -2b- provided thereon, and the nipple-7- is fixed in cooperation with the radial wing-7b-. The connecting nipple -7- has a inner thread -7a- to fix the capillary and a male cone so that the hermetically sealing of the gasket -8- fitted at the pre-column cartridge -10-, as seen in the figure 1 or at the column-1-as seen in the figure 2, can be achieved, all that to receive the axial stress of the nipple's cone -7c- as performed by the nut-6-. The pre-column cartridge -10- is housed in the lining -11-supporting the cartridge and the sealing components. A part -12- incorporating a filter component -17- is making a connection with the column -1-. The blind holes -13 and 14- allow the pre-column cartridge -10- to be included or not, as required. The invention can practically be carried out in other ways of embodiment differing only in detail from the one cited in the description by way of example. The invention can thus be manufactured in any shape or size with the most suitable materials and means as defined by the scope of the claims.

Claims: Fixing arrangement for chromatography columns comprising a connecting nipple (7) being fixable at a chromatography column (1) and being hermetically sealable therewith; a holder body (2) being releasably fixed at said chromatography column (1); and a connecting element (6) for adjustably connecting the nipple (7) to the holder body (2); characterized in that the holder body (2) has a tubular shape adapted to coaxially fit on the outer surface of the chromatography column (1) and being axially slidable on said chromatography column (1) from an unlocking position to a locking position; and a locking means (3, 13, 15) is provided for releasably locking the holder body (2) in said locking position. Fixing arrangement according to claim 1, wherein said locking means (3, 13, 15) comprises a second means (14) for releasably locking the holder body (2) in a second locking position which is closer to the nipple-receiving end of the chromatography column (1) for optionally incorporating a precolumn cartridge (10) between the nipple (7) and the chromatography column (1). Fixing arrangement according to claim 1 or claim 2, wherein each locking position is defined by respective blind holes (13, 14) provided in the outside surface of the chromatography column (1) in a distance from one another corresponding to the length of the precolumn cartridge (10), which blind holes (13, 14) are adapted to receive balls (15) located in respective bores of the holder body (2), and wherein said balls (15) are locked in the respective blind holes (13, 14) by means of a sliding sleeve (3) being in a ball-locking position; and are released by sliding said sliding sleeve (3) in a ball-unlocking position in which the balls (15) are received in blind holes (16) being formed in the inside surface of the sliding sleeve (3). Fixing arrangement according to claim 2 or claim 3, wherein the sliding sleeve (3) is urged into the ball-locking position by a flexible means (5). Fixing arrangement according to claim 4, wherein said flexible means (5) is a coil spring (5) which is supported by the axial inside of a vessel-shaped annular wall (2a) forming an axial ring groove. Fixing arrangement according to any of the claims 1 to 5, wherein the connecting element (6) is a nut (6) which engages on one side with the nipple (7) at a radial wing (7b) thereof and on the other side with a threaded portion (2b) provided at the end of the holder body (2) for adjustably forcing the nipple (7) against a gasket (8) housed in the precolumn cartridge (10) or directly at the chromatography column (1).

Inventors: SUCH QUINTANA VICENTE, TRAVESET MASANES JORDI, ZAPLANA CUNILLERA RODOLFO, SUCH QUINTANA, VICENTE, TRAVESET MASANES, JORDI, ZAPLANA CUNILLERA, RODOLFO
Applicants: TRACER ANALITICA S L, TRACER ANALITICA S.L.
Application year: 1992
Main classification: G01N30
IPC codes: G01N30