1. Field of the Disclosure
The present disclosure relates to a sample distribution device for distribution of samples in liquid chromatographs, and a device for liquid chromatography.
2. Discussion of the Background Art
Devices for liquid chromatography comprise a chromatography resin arranged in a housing. The liquid to be examined will be passed through the chromatography resin. For performing this procedure, it is known to introduce the liquid under examination at an end side of the cylindrical chromatography resin and, after chromatography has been completed, to discharge the liquid via the opposite end side. For safeguarding an equal distribution of the liquid from end side to end side, it is known to provide sample distribution devices.
Such a sample distribution device, having a disk-like shape, is known from DE 41 18 501. Said known sample distribution device comprises, in a top region thereof, a plurality of concentric annular channels connected to each other via radial channels. Said channel structure arranged in the top region is connected to the bottom region of the sample distribution device via bores extending in the axial direction. The bottom region in turn is provided with channels which, starting from the bores which are arranged on a circular line, are guided towards the inside in a star-shaped configuration. Disadvantageously, however, in this sample distribution device, the provision of channels on both sides of the sample distribution device and the provision of through-going channels which must be arranged in correspondence with said channels provided on said two sides, will cause considerable complexity and thus also high expenses.
It is an object of the disclosure to provide a sample distribution device which is as simple as possible and therefore inexpensive, as well as a corresponding device for liquid chromatography.
The inventive sample distribution device for distribution of samples in liquid chromatographs comprises a holding element provided with a sample supply channel. The holding element includes a receiving chamber, with the sample supply channel leading thereinto. In the receiving chamber, a distributing element is arranged, which in its most preferred embodiment is plate-shaped. According to the disclosure, passage openings are formed by an inner side, particularly an axially extending side wall, of the receiving chamber, and by an outer side of the distributing element opposite to said inner side. These passage openings serve for flow of the sample therethrough. For this reason, the passage openings are preferably provided on an outer side of the preferably plate-shaped distributing element. With particular preference, the inventive sample distribution device is used for chromatography resins wherein the liquid is guided to flow radially through the chromatography resin. The sample distribution device will effect a distribution of the sample, preferably from a central point of the distributing element towards the outside, whereupon the sample, when reaching the outer edge of the distributing element, will flow through passage openings formed by the inner side of the receiving chamber and by the outer side of the distributing element. Then, for instance, the sample will reach an annular, cylindrical space surrounding the chromatography resin, and will then radially pass through the chromatography resin and enter an axially extending space or channel arranged within the chromatography resin. Via said space or channel, the sample can then be discharged.
According to a preferred embodiment, the passage openings are formed by recesses in the outer side of the distributing element and/or by recesses in the inner side of the receiving chamber. For instance, the receiving chamber has a smooth, cylindrical inner side adapted to cooperate with an outer side of the distributing element that is provided with recesses, resulting in the formation of passage openings. Thus, for instance, the inventive distributing element comprises recesses exclusively on its outer side. A provision of complex channels and through-going bores is not required anymore. Thus, the distributing element can be manufactured at considerably less expense.
With particular preference, the recesses are arranged on the outer side of the distributing element in a regular configuration so as to guarantee a uniform distribution of the sample. Preferably, the recesses are formed to extend in outward directions towards the inner side of the receiving chamber. Thus, the recesses are defined in the intervening spaces between the teeth of a toothed wheel.
Between the recesses, intermediate webs are provided. At least some of the intermediate webs have suitable dimensions to the effect that the respective intermediate webs are arranged in abutment on the inner side of the receiving chamber. This makes it possible, provided that the intermediate webs have a corresponding design, to realize an automatic centering or positional definition of the distributing element in the receiving chamber, which can be effected in a simple manner.
The present disclosure further relates to a device for liquid chromatography, comprising a housing with a chromatography resin arranged therein. Connected to the housing is a sample distribution device as described above. Preferably, in this arrangement, the holding element of the sample distribution device is fastened to the housing. According to the disclosure, the distributing element is arranged at an end side of the chromatography resin and is preferably located in abutment thereon. In case of a chromatography resin having e.g. a circular cylindrical shape, the distributing element has a larger diameter so that the passage openings between the inner side of the receiving chamber of the distributing device and the outer side of the distributing element are arranged radially outside the chromatography resin. Via these passage openings, the liquid will flow into a space surrounding the chromatography resin. From this space, the liquid will pass in radial directions through the chromatography resin and will enter a discharge channel arranged within the chromatography resin and provided for discharge of the separated sample.
A preferred embodiment of the disclosure will be explained in greater detail hereunder with reference to the accompanying drawings.
A device for liquid chromatography as illustrated in
The sample distributing device 2 is fastened, by a fixing element such as e.g. a coupling nut 4 (
From chamber 52, the liquid will radially move through an outer frit 51, arranged to surround resin 44, towards the inside in the direction towards a discharge channel 48. Discharge channel 48, extending in the longitudinal direction of resin 44, is lined by an inner frit 50.
Discharge channel 48 which, as mentioned above, is oriented in the longitudinal direction of resin 44, is connected to a channel 6 formed in a discharge element 9. Discharge element 9 is fastened to housing 42 by a coupling nut or fixing element 54 in a manner similar to the attachment of sample distributing device 2.
Between holding element 8 and also holding element 12 of sample distributing device 2, on the one hand, and housing 42 on the other hand, respective sealings 52 are provided, e.g. in the form of O-rings. Further, respective sealings 53 are provided on the end sides of resin 44.
The sample distributing device 2 (
Within distributing chamber 32, the fluid is distributed in radially outward directions as schematically indicated by the arrows in
On an outer side 40 (