DE1798219B1 - CHROMATOGRAPHIC PLATE FOR THIN FILM CHROMATOGRAPHY - Google Patents

Description

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The invention relates to a chromatographic preparation of the first three components for production

Plate for thin-layer chromatography, consisting of flexible, chromatographic plates known. New

consisting of a flexible layer support and one on top of it is thus on these chromatographic plates

applied, a chromatographically active Sorp- use of an amplifying agent in the for

medium as well as a polymeric binder containing 5 chromatographic analysis layer,

trending separating layer. Since the combination of the known components should

It is known to use rather flexible, chromatographic plates for thin-layer chromatography that are not krivor-coated, to use flexible foils. In other words, all known, flexible, like foils that replace the originally customary chromatographic plates of the type described coated glass plates can be used to improve xo by adding a reinforcing agent, are z. B. by E. P. Przybylowicz and Mit- The support should be flexible and opposite the workers in the journal »Journal of Chromato- for chromatographic analysis used Lögraphy«, 20, pp. 506 to 513 (1S65). The solvents must be resistant. The support from this magazine known flexible, chrcmato- can thus ars the most different usual known graphic Plates consist of a flexible 15 th carrier. So that the flexible, chromato-carrier, for example a polyester film and a graphic plate according to the invention to be carried out thereon applied, a chromatographically active tion of various chromatographic ana-sorbents, For example, silica gel, as well as a lysing can be used, it goes without saying polymeric binder, for example polyvinyl alcohol, it is expedient that the support is made of one material hol, containing layer. 20 consists, compared to as many as possible, more usual Aufgsbe The aim is to collect such fcx: b! e, solution materials used in chro- matography Flatten to further improve, so that devices and reagents is stable. For this reason Their leeway for deviating within the framework of thin- ning is preferred as layer or film carrier layer chromatography becomes wider. mixed inert, f Im-forming materials used.

Surprisingly, it has been found that the particularly well-suited, flexible layer supports are best.

known plates right weter improve ksscn, if hen made of polyethylene terephthalate and ends according to

one of the active separating layer is given certain reinforcement covers of inert and dirrer.sicnsstabilen polyesters,

medium bucket remains. Suitable sird also z. B. Polyo! Ef nen carrier, z. B.

The task is resolved in the case of a polythene or propylene or cellulose ester, chromatographic plate of the aforementioned 30 such as cellulose triacetate, fluorine-containing, Type achieved according to the invention in that the separating polymerized hydrocarbons, such as example layer a reinforcing agent made of chemically inert, such as polytetrafluoroethylene, metal foils, for example arbitrarily oriented individual particles made of fibrous aluminum foils, and with a barrier layer, Material with an average particle size such as a polyethylene layer coated by less than about ICO microns, which is a similar 35 tetes paper. Forming a network contains. For the production of the inventive chromatographic

Surprisingly, the properties of the graphic sheets are the usual known,

this flexible, chrorratographic plate, in particular chrcrratographically active sorbent use

the coli lesion of the layer and its adhesion. on the durg fnd, for example silica gel, aluminum oxide,

flexible layer support through the reinforcing agent such as diatomaceous earth, folyamide powder and cellulose powder. There

significantly improved. Chromatographic flattening after the sorbent has been used in a finely divided form

of the invention know to be bent, or that will have to, if necessary, certain, in the trade

form cracks in the separating layer. Ferrer dismantle available sorbents before they are used.

such flats can be made smaller without damaging their edges.

work, cut and pack. The chrcmatogra- 45 The binding agent of the separating layer can likewise be obtained from the Erfrdurg by adding the reinforcement by means of an improved one from one of the usual known binding agents. Particularly suitable binders are Poly-Flexibility and Abrasion Resistance-Wahrerddiechromere based on acrylic acid, for example Polyacrylmatc graphic properties practically the same acid. Salts of polyacrylic acid, for example sodium, remain as in the case of the same chromatographic polyacrylate, polyacrylamides and homopolymers plates as reinforcing agents. U A weitererbedeuten- or Mischpoljrrerisate of Acrylsäureestern as the advantage resulting from the EXP he durg of reinforce- example Äthykcrylat, methyl methacrylate. Kung transmit results in the Trerrscbicht, is like., As these Forjmerisate are eirerseits inert and that oie eifncurgsgemiße Flatte with far thicker layers on the other hand, a particularly good binding effect could be produced than was previously possible in 55 seats. Arcere gee'grete ^B: rceirittel are both further practice was possible. e.g. Foly- (M'rylalkchol), mixtures of genes

The Flatten räch der Erfrdurg thus consist of kfne and polyvinyl alcohol), carboxymethyl cellu-

four vesertMen Eestarcteile, rfrrlxh eirem fe- lese, Foly-Cwrykcetarjharze, Polyvinylchlorid, Poly-

xible substrate, one to carry out the ethylene, polypropylene. Polystyrene, foly (vinyl acetate)

desired door content with suitable sorbents, 60 and butadiene-styrene copolymers.

Eirem for keeping the Sorpticrsmittelteils together for the production of the chromatographic

Reinforcement used to connect the layer to the carrier, according to the invention

serving as a binding agent and a reinforcing agent;

with the help of which the layer is physically reinforced, arbitrarily oriented individual parts made of fibrous or

and the sorbent particles bonded together 65 fibrous material having an average

will lie to a fraction between adjacent- particle sizes of less than about ICO microns. Of the

to prevent the particle. chemical makeup of the reinforcing agent is not

As already mentioned, the simultaneous use is critical, since there is only one in the layer

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develop physical effect. It is essential to have an average particle size of a few million, that the reinforcing agents used have those in the micron, or alternatively they can be due to the physical property limit of the Ko'loidalbereicres described above and penetrate one exhibit. average particle size of up to about 100 microns

On the pressure "chemically inert" in together 5 means have Krön.

Depending on the reinforcing agents used, the reinforcing agent particles can be made from that these against the various organic and inorganic, Chromatographic separations used natural and synthetic substances with the ge solvents and reagents are stable. As mentioned properties exist. Particularly well, however is known to the person skilled in the art, depends on the required reinforcing agents are, for example, important Resistance of the intended, natural or microcrystalline colloids The intended use of the chromatographic ma- synthetic, polymeric raw materials. Such koI- terials away. For example, all substances that are loid z. B. in one in the journal »Journal in all or most of the common organic of Applied Polymer Science ", Vol. II, pp. 481 to 498 Solvent solvents, usually mediated as reinforcement 15 (1967), by O. A. Battista and co-workers not useful if the chromatograms were published and marked with "Colloidal Macromolecular with the help of such solvents are developed Phenomena, Part II, Novel Microcrystals of Polymers « should. On the other hand, however, these substances can be described without a title. As a particularly broader one in the case of such chromatographic materials, for example, those mentioned in the above are suitable are used, the microcrystalline Celluzrm described only in special fields 20 reference Are used and, for example, only with loose and chrysotile asbestos-derived solvents or reagents against which the magnesium silicate proved. Another suitable reinforcing agent is constant, come into contact. Tonic is also a commercially available, Finally, a reinforcing agent in the fibrous, finely divided, purified wood cellulose with a Usually resistant to common solvents, not 25 particle size below 100 microns. Other uses be, if that is such a reinforcement game for suitable reinforcement means micromeans containing chromatographic material with crystalline polyamides, d. H. rod-shaped particles a commonly used eluent of small particle size with the ability to wrap must become. As a result, the resilient-grabbing or matting, z. B. microcrystalline Reinforcement agent only in combination with polyamide on adipic acid-hexamethylenediamine chain with the intended use of sis, and colloidal, rod-like alumina meaning. However, in order to be as broad as possible, microcrystals with the ability to form a network or To obtain chromatographic latitude, pre-meshwork is to be formed in a manner similar to that of preferably a reinforcing agent is used which uses the aforementioned reinforcing agents compared to most of the commonly used 35.

Resistant to solvents and reagents. Ahn- Preferably the chromatographic borrowed considerations also apply to the resistance plates according to the invention using a ability of the substrate and the polymeric binary polymeric binder and a reinforcing agent demittels to. compiled in such a way that the application of the reinforcing agents should be based on an arbitrary orientation. H. a smoldering The individual particles made of fibrous material are treated with sulfuric acid or a similar treatment. and an average particle size of less to make the chromatographic separation more colorless than about ICO microns. They are supposed to make a siebarti- connections visible. In this case be able to train the entire network. it is particularly desirable that the chromatographic By "randomly oriented" it is meant that the plate is opposed to being sprayed with concentrated sulfur reinforcing agent particles there is no need for acidic in the layer and heating to temperatures of over and over a special directional orientation at 100 ° C is resistant. This can be done easily must sit, but that each individual particle a choice of suitable polymeric binders and any suitable Can take position as long as only as a geer gain reinforcing agent. So can sample overall effect the formation of a sieve-like network 50 as a binder and acrylic acid polymers is achieved. The term "single particle" means microcrystalline magnesium silicate reinforcing agent the particles are at least for the most part used by one-cat.

are other separated and not, for example, as a particularly advantageous reinforcing means consist of a ha-material selected from long chains microcrystalline magnesium silicates ben together proven connected, individual particles is constructed under ₅₅ This is due to the fact that Magnesiumsilidem term "fibrous material" are Both cat is chemically very inert and has adsorption properties - substances with a fibrous structure as well as substances with fibers. However, this does not mean that the forming properties should be understood. The particle size of the amplifiers contained in the chromatographic plates according to the invention must be effective even as chromatographic adsorbent plates. Conventional powdered magnesia is not critical as long as these particles of silicon silicate have been found to be ineffective sufficiently small to be sufficiently small to be desirable and unsuitable as a reinforcing agent. This is to be able to act back. This means that these particles have the effect that they should be small by using microcrystalline, that they form a sieve-like network to achieve the advantages of the layer-stiffening magnesium silicate, without affecting its chemical composition or sonchromatographic properties significantly are based on the fact that it consists of individual components. The particles of the reinforcing agent are composed of a sieve-like network in the layer and can thus form colloidal dimensions, ie a work.

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The one used to make the flexible, chromatographic layer with a thickness of about 200 microns or see plates according to the invention used proportions less. By. Use of a reinforcement mitan Sorbents, binders and reinforcing agents make it practically possible to use chromatographic means are not critical. Layers of far greater thickness, up to about 500 Mierwiesen, have proven to be useful. if the separating layer is 5 crowns per part by weight, to be applied. Chro: natographic, 2 layers Sorbent about 0.02 to about 0.25 parts by weight of such thickness? thus have one considerably increased contains polymeric binder. With a much lower capacity. The thickness of the chromium binder is expedient than 0.02 parts by weight per geometric layer of flexible, one reinforcing part Sorbent possesses the layer on the chromatographic plat support containing the solvent poor adhesion and does not work according to the invention when measured in dry zuudie required abrasion resistance. Contains the stand, about 100 to about 500, useful about 250 In contrast, layer considerably more binder to about 450 microns.

than 0.25 part by weight per part by weight of sorbent. Due to its resistance, dimension part, it receives a strong corrugation and allows only stability and rigidity properties as a small migration of the solvent. Preferred layer support, preferably polyester foils, in particular contains the polyethylene terephthalate foils used for chromatographic analysis. The serving layer of a chromatographic plate support can advantageously be an electrical discharge which is highly frequent according to the invention per part by weight of sorbent, for example about 0.05 to about 0.15 parts by weight of polymeric binding, electron irradiation or a corona agent. 20 discharge, in order to increase the adhesion of the carrier. Such treatment can be used from about 0.5 to about 0.25 parts by weight. Not only with polyester filmiT, soiie; also with attached, smaller or larger fledblen films can e: follow-eici du: ch ^? iuren. Amounts of reinforcing agent are used. If the separating layer can mix the reinforcing agent in addition to the sorbent, the binding agent below 0.05 parts by weight, then it generally loses its abrasion resistance in the agent and the reinforcing agent, while layers still further, in thin-layer chromatography with an amplifying agent in amounts over conventional additives, such as, for example, phosphorescent 0.25 parts by weight, which are generally difficult to achieve smoothly, or contain fluorescent compounds. The chromatographic plates according to the invention, based on 1 part by weight of sorbent, have a smooth appearance and are free from tel, in amounts of about 0.10 to about 0.20 weight errors, such as holes or in a guideline used. coating lines showing direction. The chromatographic application of the separating layer to the layer- phically active layer adheres firmly to the layer support can be carried out according to customary known methods, the layer not following when the plate is bent. For example, the sorbent may break or peel off. Chromatographic plates containing the binder and the reinforcing agent in accordance with the invention can be processed, cut to produce a slurry in an amount sufficient to be applied and packaged without damaging their edges. Furthermore, the chromatographic water can be slurried and the slurry plates obtained according to the invention with thicker chromatonization on the layer support can be produced with the aid of a coating graphic layer than was previously possible using a roller. In this way, the chromate coating or funnel coating applied to graphic plates according to the invention will be larger. Preferably, the sorption capacity will be used first. The migration of the solvent in the separating layer, the binder and the reinforcing agent, is moistened with the chromatographic platinum water and then thoroughly mixed, not inappropriately according to the invention in order to obtain a homogeneous dispersion. A suitably handicapped or delayed. During the migration of the Lönetes process, for example, a cooling agent does not dissolve and neither the chromatographic gel mill is charged with the sorbent, nor does the Löauf add considerable amounts of contaminant to an aqueous suspension of the reinforcing agent The resulting mixture was taken along with several genes that would be ground on the solvent front to form a spot for minutes, which would then lead to aqueous formation. By appropriately dispersing the binder and choosing the individual components, the chrome mixture can be ground again for several minutes. 55 matographic plate according to the invention both

The one used for chromatographic analysis against destruction, by means of visualization as

The layer can be placed on the support in any desired manner - also against the usual ones in chromatography

resistant to solvents and reagents up to a thickness of about 500 microns,

be applied. The following examples are intended to further illustrate the invention

In the usual thin layer chromatography with 60 illustrate

an adsorption agent distributed on a glass plate. Example 1 top layer possesses the latter in the moist state in the

Typically 250 microns thick. Commercially available 85g of silica gel, 10g of microcrystalline magnesium prefabricated glass plates usually contain a silicate (consisting of a colloidal, rod-shaped chromatographic layer with a thickness, measured 65, and particles obtained from chrysotile asbestos with a dry state, 250 microns. The previous particle size of less than 1 micron , a bulk available, flexible, chromatographic plate density of 96.2 g per liter and a surface area of usually contain a chromatographic 70 m ² / g) and 5 g of polyacrylic acid were in 450 ml

Slurried water and blended in a blender for 10 minutes. The pH of the slurry was then adjusted to 7 by adding sodium hydroxide. The resulting slurry was by hand using an adjustable coating bar with a tongue setting of 0.635 mm olie applied and then dried in an oven for 30 minutes at 100 ⁰ C on a flexible, pre-exposed to an electron bombardment Polyäthylenterephthalatf. The chromatographic layer thickness of the obtained chromatographic material was about 250 microns as measured in the dry state. The chromatographic separating layer adhered firmly to the support. The chromatographic plate cut on a cutting table without peeling of the edges. Furthermore, the plate obtained could be folded without cracks occurring in the separating layer.

In contrast, the edges of a peeled both in terms of structure and in terms of the thickness of their chromatographic layer comparable to the chromatographic plate which did not contain any reinforcing agent when this panel was cut on a cutting table. This chromatographic plate could also not be folded without causing severe cracking came in the chromatographic layer.

Example 2

A 3.78 1 capacity ball mill, about one third of which was filled with stone balls, was used with 500 g of aluminum oxide and 1000 ml of distilled water are filled. The alumina slurry was ground at a speed of rotation of 60 rpm for 20 minutes to obtain the aluminum oxide down to the size required for thin-layer chromatographic separation. The resulting slurry was then transferred to a mixer and weighed 167 g an aqueous dispersion of 25 g of sodium polyacrylate was added. After mixing for 5 minutes 50 grams of microcrystalline magnesium silicate was added and mixing was continued for an additional 5 minutes. The received Slurry was then returned to the ball mill and tumbled for 12 hours, to remove the air trapped during the mixing process. Contained during the agitation the ball mill no stone balls. Using the slurry prepared in the manner described and using the support described in Example 1 was after that in Example 1 method described a chromatographic plate with a chromatographic Separation layer made with a thickness of 250 microns. The chromatographic The plate could be cut without damaging the edges and without cracking the chromatographic Bend layer. A corresponding chromatographic plate of the same thickness, but without Reinforcement agent, could neither be cut without damaging the edges nor without cracking in the chromatographic layer can be bent.

Example 3

50 g of silica, 1.8 g of sodium hydroxide and 100 ml of water were placed in a ball mill and Grind for 15 minutes. The resulting slurry was then transferred to a mixer and with 75 ml of water and 12 g of a 25 percent strength by weight aqueous solution of polyacrylic acid offset. Then 6 g of microcrystalline were added to the mixer with continuous stirring Magnesium silicate filled. After adding the microcrystalline magnesium silicate The resulting mixture was transferred to a large vessel and circulated for 30 minutes to remove the enclosed To remove air. With the slurry prepared in the manner described and using The film support given in Example 1 was prepared according to the method described in Example 1 a chromatographic plate with a chromatographic layer 550 microns thick manufactured. The chromatographic plate thus obtained could be opened without damaging the edges cut and bend without cracking in the chromatographic layer.

A corresponding chromatographic plate with a chromatographic layer of the same thickness, but without reinforcing agents, could neither be cut without damaging the edges nor without Cracks in the chromatographic layer are bent.

Similar results were obtained when other commercially available microcrystalline magnesium silicates were used, for example those with a higher bulk density, e.g. B. a bulk density which can be twice as large as the bulk density of the magnesium silicate used in Example 1 or those with a larger surface area of up to 120 m ² / g and above or those with a smaller particle size.

Example 4

A ball mill was charged with 10 grams of wood cellulose (a fibrous, finely divided, chemically purified wood cellulose) consisting of particles about 100 microns long and about 1 to 2 microns in diameter, 150 ml of ethanol and 150 ml of water. After one hour of grinding, 85 g of silica, 4 g of calcium silicate activated with lead and manganese, 0.5 g of sodium hydroxide, 25 ml of ethanol and 25 ml of water were introduced into the ball mill, followed by grinding for a further hour. The mixture obtained was then transferred to a mixing device and 5 g of pulverized polyacrylamide were added with stirring.
With the coating composition prepared in the manner described and using the support described in Example 1, a chromatographic plate with a chromatographic separating layer having a thickness of 250 microns was produced by the method described in Example 1.

The chromatographic plate thus obtained could also be cut without damaging the edges and bent without cracking in the chromatographic layer.

A corresponding chromatographic plate with a chromatographic layer of the same thickness, but without reinforcing agents, it could not be cut without damaging the edges or without cracking be bent in the chromatographic layer.

B e i s ρ i e 1 5

To a dispersion of 85 g of silica gel in 275 ml of distilled water, 5 g of powdered poly-

109 524/271

acrylamide and 10 g of microcrystalline cellulose (microcrystalline cellulose, consisting of rod-shaped Particles with a particle size in the range between below 1 and 100 microns and an average Particle size of 38 microns) was added. The resulting mixture was mixed until a smooth homogeneous one Slurry was obtained.

With the slurry prepared in the manner described and using that in the example 1 specified layer support was according to the method described in Example 1, a chromatographic Plate made with a chromatographic layer 250 microns thick. the The chromatographic plate thus obtained could be cut without damaging the edges and without cracking be bent in the chromatographic layer.

A corresponding chromatographic plate with a chromatographic layer of the same thickness, but without reinforcing agents, it could not be cut without damaging the edges or without cracking be bent in the chromatographic layer.

Similar results were obtained when other types of microcrystalline were used as reinforcing agents Cellulose, d. H. celluloses manufactured by various companies were used.

Claims (12)

Patent claims: 1. Chromatographic plate for thin-layer chromatography, consisting of a flexible one Layer support and one applied to it, a chromatographically active sorbent as well as a separating layer containing polymeric binder, characterized in that that the separating layer is a reinforcing agent composed of chemically inert, randomly oriented individual particles of fibrous material having an average particle size less than about 100 microns, which form a mesh-like network. 2. Chromatographic plate according to claim 1, characterized in that the amplifying agent is microcrystalline magnesium silicate. 3. Chromatographic plate according to claim 1, characterized in that the amplifying agent is microcrystalline cellulose. 4. Chromatographic plate according to claims 1 to 3, characterized in that the chromatographically active sorbent is silica gel. 5. Chromatographic plate according to Claims 1 to 4, characterized in that the polymer The binder is an acrylic acid polymer. 6. Chromatographic plate according to claims 1 to 5, characterized in that the flexible Layer carrier consists of a polyester film. 7. Chromatographic plate according to Claims 1 to 6, characterized in that the flexible Layer support consists of a polyethylene terephthalate film. 8. Chromatographic plate according to Claims 1 to 7, characterized in that the separating layer per part by weight of sorbent from about 0.02 to about 0.25 parts by weight of polymeric binder contains. 9. Chromatographic plate according to Claims 1 to 8, characterized in that the separating layer contains about 0.05 to about 0.25 parts by weight of reinforcing agent per part by weight of sorbent. 10. Chromatographic plate according to claims 1 to 9, characterized in that the chromatographically active separating layer on the polyethylene terephthalate film made of silica gel in one Thickness of about 100 to about 500 microns, and per part by weight of silica gel about 0.02 to about 0.25 parts by weight of sodium polyacrylate and about 0.05 to about 0.25 parts by weight of microcrystalline Contains magnesium silicate. 11. Chromatographic plate according to claim 10, characterized in that the chromatographically active separating layer instead of sodium polyacrylate about 0.02 to about 0.25 parts by weight of polyacrylic acid contains per part by weight of silica gel. 12. Chromatographic plate according to claim 10, characterized in that the chromatographically active release layer instead of sodium polyacrylate about 0.02 to about 0.25 parts by weight of polyacrylamide per Contains part by weight of silica gel.